Plasma is an electrically conductive gas containing highly reactive particles such as radicals, atoms, plasma electrons, ions and the like. For example plasma may be formed when atoms of a gas are excited to high energy levels whereby the gas atoms lose hold of some of their electrons and become ionised to produce plasma.

Background Thermal plasma including plasma arc is known. However plasma arc is associated with high power consumption, the rapid erosion of electrodes when used in electrolysis, the need for catalysts and high-energy loss due to the associated high temperatures.

Summary of the invention According to a first aspect of the present invention, there is provided a method for generating plasma in a fluid, comprising the steps of providing a fluid, introducing and/or generating one or more gas chambers or bubbles within the fluid, whereby the chambers or bubbles are contained by the fluid, and treating the fluid such that a plasma is generated within the chambers or bubbles.

The applicant has discovered that a plasma can be generated relatively easily within bubbles within an aqueous medium. This plasma causes dissociation of molecules and/or atoms which can then be treated and/or reacted to obtain beneficial reaction products and/or molecules and/or atoms.

The liquid containment means may be open to the atmosphere and the process may therefore be carried out at substantially atmospheric pressure.

Alternatively the containment means may be contained within a sealed reaction chamber, e. g. under partial vacuum. This reduction in pressure can reduce the energy required to achieve a glow discharge within the bubbles passing over a cathode.

Importantly the process is not required to be carried out in a vacuum.

In a particularly preferred form the liquid containment means is a bath, e. g. a rectangular bath having an open top. However it will be clearly understood by persons skilled in the art that a variety of configurations can be used.

The plasma may be formed, for example, by applying a potential difference to the fluid, preferably by means of electrodes.

Upon passing electricity of sufficient potential between two electrodes, the dielectric barrier associated with the bubble/chamber surface breaks down, with the accompanying formation of plasma discharge inside the gas bubbles or chambers.

This enables plasma formation to be effected at very low voltages, current, temperature and pressure, as compared with known methods of plasma formation.

For example, typical voltages and currents associated with plasma arc are in the region of 5KV and 200 A respectively, whilst in the present invention, a plasma my be provided with a voltage as low as 350 V and a current as low as 50 mA.

The formation of a glow discharge region adjacent said one electrode is caused by a dielectric breakdown in the bubbles surrounding the electrode. The bubbles have a low electrical conductivity and as a result there is a large voltage drop between the electrodes across this bubble region. This voltage drop accounts for a large portion of the overall voltage drop across the electrodes. The plasma is generated within the bubbles contained within the electrolyte. This serves the purpose of the liquid electrolyte acting as containment for the plasma within the bubbles.

According to the present invention, the inventor has shown that the voltage needed for plasma generation is much lower than plasma glow discharge generated under gas only conditions. For example experiments have demonstrated that plasma begins to occur at voltages as low as 350V and the max. voltage required with various liquids should be within 3000V. This requirement is based on a current

density of 1 to 3 Amp/cm2 which can be achieved at the point of discharge whereby the current input ranges from 50 to about 900mA.

Plasma can be created, according to the present invention, in a steady manner with low voltage and current supply, which leads to an economy in power consumption.

The bubbles or gas chambers may be produced by any suitable means, for example electrolysis, electrochemical reaction, electrode heating, releasing of trapped gases in the liquid, ultrasonic cavitations, laser heating, and externally introduced gases or a combination thereof. For example, corona discharge and or glow plasma discharge takes place inside the bubbles or gas chambers present in the liquid. Passing electricity of sufficient potential through the liquid causes the electric breakdown of the dielectric bubble barrier with the associated formation of plasma discharge inside the bubbles/. gas chambers.

The bubbles may contain precursor materials originating in the, which liquid is preferably a liquid, more preferably being an aqueous electrolyte. This material may have been transferred from the liquid to the bubbles by diffusion or evaporation.

Alternatively the precursor may be introduced directly into the bubbles from outside the system.

The step of generating bubbles within the aqueous medium may be accomplished by one or more of the following : electrolysis, ebullition, ultrasonic cavitations, entrainment, sparging, chemical reaction, dissociation by electrons and ion collisions or local heating or ebullition, hydraulic impingement, ultrasonic waves, or laser heating.

. Electrolysis bubbles may be generated by the electrode as a result of the potential differences applied thereacross, e. g. hydrogen bubbles liberated by the cathode or oxygen bubbles liberated by the anode. Ebullition bubbles may be generated by electrical heating in the region of the electrodes. The bubbles may be generated by direct electrical heating or by heating in proximity to the electrode by a moving wire or grid. Microwave heating and heating using. lasers may also be used to generate ebullition bubbles.

Cavitation bubbles may be generated by using an ultrasonic bubble generator or a jet of fluid or a jet of a mixture of gas and liquid injected into the electrolyte in proximity to the electrode. Cavitation bubbles may also be generated

by hydrodynamic flow of the electrolyte in proximity to the electrode. Sparging of gas in proximity to the electrode may also be used to generate bubbles.

Bubbles may also be generated by a chemical reaction which evolves gas as a reaction product. Typically such reactions involve thermal decomposition of compounds in the electrolyte or acid based reactions in the electrolyte. Bubbles may also be formed in the electrolyte by adding a fother thereto.

Typically the generation of bubbles forms a bubble sheath around said one electrode. The bubble sheath may have a thickness of from a few nanometres to say 50 millimetres. Typically the bubble sheath may have a thickness of 1 to 5 mm.

Further it should be understood that the bubbles may not be homogeneous throughout the sheath.

Gas or vapour formed external to the container may be pumped or blown into the aqueous medium in proximity to the cathode.

Thus the composition of the plasma that is generated within the bubbies-may be tailored to suit the application to which the plasma is being put and the. bubbles may either be generated within the plasma or introduced into the liquid from outside the containment means.

The bubbles can assume various sizes and shapes and may exist in other than the traditional spherical bubble, for example by assuming a sheet form air gap or air pocket covering shrouding the electrodes or spread across the liquid media in micro bubbles. Liquid foam may also be considered to be bubbles or gas chambers for the purposes of the present invention, this being highly concentrated dispersion of gas within a continuous interconnecting thin film of liquid. The gas volume can reach up to 80% of a contained area whereby gas generated within or introduced to the reactor externally can also be encapsulated within a foaming agent, for example, to undergo plasma discharge treatment.

Gases trapped inside a thick liquid mist in a confined space are also considered to be gas containing bubbles, which contain the gases, and liquid vapors that provide the condition for generation of non-thermal plasma. The liquid will contribute as part of source materials for dissociation during plasma discharges.

In practise, gas bubbles evolving near and shrouding an electrode in an electrolysis process create a dielectric barrier which prevents and slows down the flow of current. At the same time the dissolved gas or micro bubbles spread and

defuse in the liquid volume thereby creating a high percentage of void fractions (micro gas bubbles) which in turn increase the electric resistance whereby the voltage across the liquid media is raised. When the voltage has increased sufficiently, gas trapped inside the bubbles undergoes non-equilibrium plasma transformation. At this point, electric breakdown occurs enabling resumption of current flow through the bubbles sheath or air pocket layer. In the case of water electrolysis, production of hydrogen will be resumed which would otherwise have been slowed down by the present of bubble barrier.

When plasma discharge occurs, any water vapor inside the bubbles will experience plasma dissociation whereby H+, OH-, O-, H, H3, and other oxidative, reductive and radicals species are formed. The formation of charged plasma species will of course also depend on the chemical composition of the electrolyte.

Any water molecules and atoms lining the gas and liquid interface of a bubble shell will also be subjected to the-influence of the plasma-to produce H+ and OH-and other radical species. Some of these neutralized atoms and molecules will transpose into the gas bubbles as additional gas that increases the size of the bubble. As such the bubbles pick up more liquid vapors before a next succession of plasma discharge. Such a cycle of such repetitive discharge can take place in fraction of second to several second depending on the make up of the electrode and reactor.

The step of generating bubbles within aqueous medium may include adding a foaming agent to the aqueous medium such that bubbles are formed within foam.

The foam bubbles are confined by aqueous media that is electrically conductive. The foam bubbles can vary widely in size down to a fraction of a millimetre.

The step of generating bubbles may include forming an aerosol mist. The gas within the aerosol mist broadly defines bubbles in the sense that there is volumes of gas between liquid droplets. These bubbles in the form of spaces between liquid drops function in a similar way to conventional bubbles within a liquid and a plasma is formed in this gas in the same way as described above.

An advantage of foam and aerosol mist is that it provides for good mixing. of gaseous components within the mist and foam. The plasma is generated in the bubbles of the foam and aerosol mist in the same way that they are formed in an aqueous liquid, e. g. by passing electrical current between spaced electrodes within the foam or mist.

The step of forming a glow discharge in the bubble region may be achieved by increasing the potential difference across the electrodes above a certain threshold point.

The formation of a glow discharge and generation of plasma within the bubbles may be assisted by a pulsed or steady power supply, a magnetron field, ultrasonic radiation, a hot filament capable of electron emission, laser radiation, radio radiation or microwave radiation. The energy requirements may also be assisted by a combination of any two or more of the above features. These factors may have. the effect of lowering the energy input required to reach the threshold potential difference at which glow discharge is formed.

In conventional electrochemical processes bubbles are regarded as undesirable. As a result concerted efforts are made to avoid the generation of bubbles during the operation of electro-chemical cells. By contrast the process of the current invention-deliiaerately fosters the formation of bubbles and utilises bubbles in proximity to the electrode as an essential feature of the invention. The bubble sheath surrounding the electrode is essential to establishing a plasma region which then gives rise to the plasma deposition on the article.

Thus the plasma is formed within bubbles and the molecules and/or atoms that are ionised are surrounded by liquid which effectively provides a containment structure within which the plasma is contained. The liquid in turn generally opens to the atmosphere.

Plasma glow discharge can be fairly easily accomplished within the cell because the sheath of bubbles has the effect of causing a substantial proportion of the voltage drop to occur across the bubble sheath. It is concentrated in this area rather than a linear drop across the electrode space. This provides the driving force to generate plasma glow discharge and from there deposition of the ionic species.

The electrical charge is preferably applied in pulses, since this enables plasma production at lower voltages.

The fluid is. preferably a liquid electrolyte, for example an aqueous medium, whereby in one preferred embodiment, the medium is water.

The electrolyte may comprise a carrier liquid and/or a source or precursor of the material to be ionised by the plasma.

When the liquid is water, charged plasma particles include species such as OH radicals, 0-and H+,-OH, 02 and 03, which will react with the surrounding liquid.

Distilled water is known to be dielectric and non-conductive. It is however when water contains impurities such as dissolved minerals, salts and colloids of particles, whereby water becomes conductive, that ionisation and electrolysis can occur.

The method may further include adding an additive, such as an acidic or alkaline conductivity enhancing agent, to the aqueous medium to enhance this electrical conductivity such as organic salts or inorganic salts, e. g. KCI, MgCI2, NaOH, Na2CO3, K2CO3, H2SO4, HCI.

The method may include adding a surfactant to the aqueous medium for lowering the surface tension of the medium and enhancing the formation of bubbles, e. g. to stabilise bubble formation.

The electrolyte may further include additives in the form of catalysts for increasing the reaction of molecules and/or atoms produced in the plasma, additives for assisting the formation of bubbles, and additives for buffering the pH.

The method may further include cooling the electrolyte to remove excess heat generated by the plasma reaction and regulating the concentration of one or more components within the electrolyte.

The cooling may comprise drawing electrolyte from the bath pumping it through a heat exchanger, and then returning it to the bath.

Plasma creation, according to the present invention can be effected in the absence of extreme conditions, for example plasma according to the present invention may be provide under atmospheric pressure and at room temperature.

During plasma production according to the present invention, a shroud of bubbles preferably builds up and smothers around at least one of the electrodes, whereby electrical charge builds up in the bubble shroud thereby creating a dielectric barrier which impedes current flow, whereby electrical resistance in the fluid medium builds up so that voltage through the medium is raised to a degree such that gas within the bubbles is excited to an energy level at which a plasma is produced.

The method according to the present invention preferably comprises the further step of exposing the plasma to a material, which on contact with the plasma undergoes a chemical and/or physical change.

For example the plasma can be used to cause dissociation of toxic compounds and then break down the compounds and/or cause them to undergo reactions leading to innocuous reaction products The plasma produced according to the present invention, which will be referred to as'under liquid'plasma has the same physical and chemical properties as plasma produced according to known methods and accordingly also has the utility of such plasma.

The under liquid plasma according to the present invention can create an active catalytic condition which facilitates gas and liquid interaction. As such, the plasma according to the present invention, may any reaction which takes place in a liquid medium, for example chemical reactions, the production of pharma-ce-uticais, production of nano-particles, the extraction of metals from liquid, low temperature sterilization of liquid food, use in paper industries to decontaminate the effluent discharge, fragmentation or de-lignifications of cellulose ; the removal of odor from discharging liquid in the food industries, and the treatment of fluid effluent. Material may be chemically modified by means comprising one or more of the following : ionisation, reduction, oxidation, association, dissociation, free radical addition/removal, whereby, optionally, following chemical modification, the material is removed.

The invention foresees a number of utilities which tackle existing problems.

For example, water that has been used in industrial processes or used in some other way could be treated to remove harmful components before it is returned to ground water. Many of the foreign or undesirable components can be treated in conventional fashion to reduce their potential for harm. This is typically achieved by reacting the harmful components with other chemical components introduced to the water to form relatively harmless products. Many undesirable components are treated fairly effectively in this way.

However some harmful components within water are not capable of being treated in this fashion. This poses a problem as these harmful components, e. g. contaminants, need to be removed from the water before it is returned to ground

water. One way of treating some of these components is to use an electric arc process to break down these toxic chemicals. However an electric arc process requires a substantial amount of energy to arc between electrodes within the liquid and is therefore costly. In addition the number of chemicals that are able to be treated in this way is limited. A further limitation of these processes is that they often cause rapid consumption and degradation of electrode material.

Moreover the electric arc method of providing plasma applies a high voltage across closely spaced electrodes causing the break down and ionisation of molecules, and then a surge of electrical current between the electrodes.

Further many metals or mineral occur naturally in the ground in the form of ores as mineral oxides. The minerals need to be reduced-to useful minerals.

Typically the reduction is carried out using pyrometallurgical techniques, e. g. such as are used in electric arc furnaces. These treatments are very aggressive and utilise enormous amounts of electrical energy.--Clearly it wouid be advantageous if a simpler more streamlined and more energy efficient method of reducing a mineral oxide to a mineral could be devised.

Yet further the generation of electrical energy with fuel cells is seen as an exciting new area of technology. Such fuel cells utilise hydrogen as a fuel.

Accordingly a relatively inexpensive source of this hydrogen as a fuel is required.

Currently hydrogen is produced by solar cells, however the present invention aims to provide such a source of hydrogen and solve one or more of the above referred to problems.

In one form of the current invention, the undesirable compounds may be deposited on a said electrode, e. g. the cathode, as a layer or coating. The compound can then be removed from the liquid by simply removing it from the aqueous medium.

In another form, the undesirable component can be reacted with a chemical compound, e. g. within the plasma, to form a solid compound, e. g. a salt in the form of a precipitate, that settles out of the aqueous medium and can then be removed from the aqueous medium.

Typically the undesirable component will be toxic to animals or harmful to the environment. However components that are undesirable in other ways are also included within the scope of the invention.

Applicant envisages that this aspect of the invention will be particularly useful for the removal of harmful heavy metals from waste water. It will probably also be useful for the treatment of contaminated gases. Such gases will be introduced to the aqueous medium in such a way that they form part of the bubbles passing over the cathode and then be treated as described above.

Another example is the extraction of a mineral, e. g. a metal, from its metal oxide, the method including : dissolving the mineral oxide in an aqueous medium and then subjecting it to the method described above according to the first aspect of the invention whereby a plasma is generated within bubbles passing over the cathode, and the plasma reduces the mineral oxide to the mineral perse.

The ozone that is formed in the plasma can then be reacted with hydrogen to form an innocuous compound such as water. The reduced mineral that is formed in the plasma, e. g. a metal, may be deposited on the cathode or else may be precipstaied out as a solid in the containment means. in the case of water, hydrogen and oxygen produced, travel to the anode and cathode and are preferably then removed. As such, the process according to the present invention is an economical, simple and effective way of producing hydrogen.

The hydrogen produced in this fashion may be used as fuel, e. g. in fuel cells for the generation of electricity. Applicant believes that hydrogen can be produced relatively inexpensively in this fashion. Fuel cell technology is currently receiving an increased level of acceptance looking for a cheap source of the supply of hydrogen.

According to another aspect of the present invention there is provided the use of this'under liquid'plasma in one or more of the following : chemical and/or physical treatments of matter, electrolysis, gas production, in particular hydrogen gas production; water, fluid and/or effluent treatment; mineral extraction; sterilization of drinking water and/or liquid food, production of nano-particles, the enhancement of material chemical and physical properties.

According to a further related aspect of the present invention there is provided an apparatus for providing a plasma comprising; a container in which a plasma is provideable, bubble trapping means, arranged within the container, for trapping gas bubbles at a predetermined location in the container and, plasma creation means, in association with the container, for creating a plasma from the gas within the bubbles.

A known problem with carrying out electrolysis is that any gas/bubble build up in the electrolytic cell creates a barrier to the flow of current through the electrolyte, thereby impeding electrolysis, which increase in resistance in turn forces the required voltage up. As such, electrolytic cells require a great deal of energy and are often very large in order to effect dispersion of such gas/bubbles. However the present invention actively promotes such bubble build up, in order to effect plasma creation which the inventors have shown is effective in carrying out electrolysis.

The plasma creation means preferably comprise electrical discharge means which most preferably comprise a cathode and/or an anode.

The apparatus, in one preferred embodiment being an electrolysis cell, further preferably comprises bubble introduction and/or generating means, for introducing and/or generating bubbles in the container.

Furthermore the apparatus preferably comprises one or more of the following: enhancing means for enhancing plasma formation and one or more non-conductive partitions arranged between the electrodes, whereby the enhancing means preferably comprise bubble trapping means most preferably associated with the electrodes and wherein the enhancing means may also comprise current concentrating means for concentrating the electrical current at a predetermined position in the container which can take the form of one or more channels arranged through one or more of the electrodes.

The electrodes may take any suitable form, for example the electrodes may be so profiled as to entrap/attract bubbles, in order to help gas bubbles being created or introduced to the discharging electrode to form a dielectric barrier by which the voltage can be raised whereby a suitable current density is provided directly by high input of current or passively created by a current concentrating arrangement, for example, by conducting the current through small holes on the electrodes or by reducing the discharge surface area of the electrodes whereby in the latter case, the electrodes may take the form of pins, wires, rods and the like.

For example, the cathode may be formed. by a hollow tube with perforated holes therein, e. g. small perforated holes. The holes allow bubbles introduced into the tube to pass out of the tube into the aqueous medium. Alternatively a cathode may be made of wire mesh or have a roughened surface, e. g. to encourage the attachment of bubbles thereto to slow down the movement of the bubbles.

In one embodiment there are a plurality of cathodes spaced apart from each other and in parallel with each other, and a single rod-like anode, e. g. centrally positioned relative to the cathode.

The other electrode (non discharging) preferably has a larger surface area such than the discharging electrode.

The discharging electrode can either be cathode or anode depending on the application necessity.

In an experimental reactor the separating membrane, non-conductive partition, was nylon cleaning cloth having a tight matrix 0.5mm thick. This semi-permeable membrane is capable of resisting the passage of oxygen and hydrogen ions therethrough in the aqueous medium, intermediate the anodes and cathodes thereby to maintain separation of oxygen and hydrogen produced in the plasma.

Most preferably, the apparatus according to the present invention is an electrolytic cell.

Detailed description of the invention The present invention relates to the production of non-thermal plasma contained in a liquid by generating corona discharge and or glow plasma discharge inside the bubbles or air pockets present in the liquid.

Upon passing electricity of sufficient potential through the liquid, electric breakdown of the dielectric bubble barrier results in the formation of plasma discharge inside the gas bubbles or pockets present in the liquid. In most cases glow discharge occurs near the electrodes but occasionally glow discharge is also observed away from the electrode.

The bubbles can be produced either by the electrolysis, electrochemical reaction, heating of electrodes, releasing of trapped gases in the liquid, ultrasonic cavitations, laser heating, and externally introduced gases. This differs from the way transient bubbles are created by an electric discharge through a sparking device or thermal dissociation in the arc plasma. In practice the bubbles could be created in combination of a number ways described above.

Bubbles produced by electrolysis of water contain hydrogen gas at the cathode and oxygen gas at the anode. Such bubbles can also contain other chemical vapors originating from the electrolyte or additives thereto.

The liquid serves as an electrolyte which provides conductivity of electricity, the source material from which gases and vapour are produced for plasma dissociation to form, for example, reduction and oxidation, radicals and neutral species. The liquid also provides an active catalytic chemical environment for forming new compounds. It also serves as containment of gases in the form of bubbles or air pockets in which the non-thermal plasma discharge takes place.

In practise, gas bubbles evolving and shrouding the electrodes during electrolysis create a dielectric barrier which inhibits the flow of current.

At the same time the dissolved gas or micro bubbles spread and defuse in the liquid volume create a high percentage of void fractions (micro gas bubbles) which also increase the electric resistance and so raise the voltage across the liquid media.

When the voltage between two electrodes reaches a critical level, the gas trapped inside the bubbles undergoes non-equilibrium plasma transformation. This is also known as electric breakdown which enables the resumption of current flow through the bubble sheath or air pocket layer. In the case of water electrolysis, the production of hydrogen will then resume.

During plasma discharge, light emission may be observed in the bubbles in a sporadic or steady manner in short and continuous flashes near the surface of the electrodes and in the liquid media.

Continuous light spots may also be observed in areas distanced from the electrodes where suspected small air bubbles are trapped and yet remain under the influence of strong electrical field.

The temperature in the electrolyte near the electrodes has been measured to be-in the region of 50 to about 90°C with an experiment running in water for 30 minutes, which indicates that the plasma is non-thermal plasma.

The temperature variation may be influenced by electrode geometry, electrolyte concentration, level of inception voltage and current density for the glow discharge. The temperature measured directly over the discharging electrode can reach over 200°C during reformation of methanol for example Configurations of electrodes, size, spacing, dielectric barrier coating, electrolyte temperature, current density, voltage and reactor geometry are factors influencing plasma formation.

Special structure and arrangement to retain gas or gas bubbles close to the electrodes provide favorable circumstances for the ready formation of a steady and cyclical plasma glow discharge with lower voltage and current input.

Electrodes configuration can be in following forms: such as plate to plate, plate to pinned plate, dielectric coated plate to plate or pinned plate or both, wire mesh to plate, wire mesh to wire mesh or to perforated plate, wire or groups of wires in perforated cylinder tube, tube in tube and etc. in single or multiple arrays.

Many more combinations of electrode configurations are conceivable, such as sponge porous metal electrode, electrode covered with honey comb non conductive materials and porous ceramic filter to entrench gas or using non-conductive plate with drilled holes and gas traps that retain gas bubbles and concentrate the current density next to the electrode surface.

In general keeping the bubbles close to the electrodes'surface can also be achieved by attaching a porous nonconductive nylon foam mattress and/or a honeycomb or porous ceramics slab of suitable thickness, so that the mobility of the bubbles is slowed down and at the same time the conduit for current flow is narrowed by a shading effect of the dielectric materials which in turn raises the current density locally.

For the same reason glass beads, plastic beads and beads of catalytic material ie. Ti02, graphite of suitable size can be placed between the electrodes in order to slow down the flow of bubbles.

A non conductive, heat and corrosion electrode covering material, structured to retain and trap gas bubbles which also concentrates current density through small

openings arranged therethrough whilst providing an adequate exposed electrode surface for electro-chemical and electrolysis reactions, improves the generation of steady and short cyclical under liquid plasma discharge.

Multiple layers of very fine stainless mesh sandwiched between two plastic cover plates with small perforated holes have produced a steady glow plasma. The void space created by the layered wire mesh provides a trap for air bubbles as well as enlarging the contact surface for electro-chemical and electrolysis reaction.

In an experiment both vertical or horizontal electrodes were covered and bonded with non conductive materials (plastic) with patterned perforation to trap gas bubbles and at the same time allowing fro electrical contact of the electrodes through the perforation.

The electrode contact surface was enlarged underneath the shielding to increase gas production during electrolysis or heating. Current flow was concentrated through small hole of 1 to 3mm leading to the trapped gas and bubbles, which underwent plasma transformation. Cyclical and steady plasma was observed with an input DC voltage ranging from 350V to 1900V and current ranging from 50mA to 800mA.

A non-conductive diaphragm, which does not restrict the free flow of ions and electrolyte, placed between two opposite electrodes to prevent crossing of bubbles between two half electrolytic cells avoids remixing of the gases which have been separated by electrolysis is preferable.

A reactor may be so structured that the electrolyte is able to enter into the reactor through the separating membrane or opening form in the reactor to replenish the lost of electrolyte within the enclosed reactor.

There are other techniques which can be incorporated into the proposed invention for the enhancement. of plasma generation such as pulsed power supply, RF power, microwaves, ultrasonic waves, magnetron field, laser. Some of the above techniques may also be applied in pulsed form.

Ultrasonic cavitations in liquid (sonic-technology) is an important enhancement method, which will enhance the plasma formation and the catalytic reaction that benefit a number of under liquid plasma applications.

The under liquid plasma requires for example an input of DC or AC voltage in the range from 350V up to 3000V and current density ranging from 1 Amp to 3 Amp per cm2 in dealing with a large range of liquid media.

The voltage and current requirement depends very much on the chemical and physical properties of electrolytic liquid as well as those factors mentioned above.

The under liquid plasma method according to the current invention can operate at atmospheric pressure and ambient temperature, however an external pressure less than one atmosphere or over one atmosphere with higher temperatures does not deter the generation of plasma in the bubbles. A higher temperature in the liquid also means more active gas molecules within the bubbles, which can benefit plasma formation.

Non-thermal plasma generated in a liquid according to the present invention has advantages over known plasma discharge for example in gas, under water plasma arc and pulse power electric discharge, being: - It requires only simple electrolytic cells to be the reactor to perform such discharges There is little erosion to the electrodes and wider range of electrode materials can be chosen such as stainless steel, graphite, aluminium and good conductive materials which are resistance to chemical erosion. The polarity of the electrode can be reverted if necessary to compensate the lost of electrode materials if so desired.

- It works under one atmospheric pressure and ambient temperature. The liquid electrolyte will be primary source of materials for the chemical and physical reaction take part in the process. There are number. of ways that bubbles can be produced within the electrolytic cell. Gas can also be introduced to the reactor where plasma catalytic and dissociation is taking place.

- It is a low temperature system as the plasma discharge is non-thermal. Any excessive or undesirable high temperature can be cooled down by increasing the

circulation rate of the liquid which can lose its temperature through heat exchange. Heat generated can be recovered as secondary energy.

The electrolyte (liquid) will serve as extension of the conducting electrodes in contact with the gases or vapor trapped inside the bubbles. The air gap between two electrodes is reduced to the thickness of the gas bubbles or air pocket which thus enables plasma discharge at a much lower voltage and current compared with other plasma discharge system. Plasma glow discharge, according to the present invention, can be initiated under a conditions at voltage as low as 350V and the current ranging from 50 to 800mA. Extra energy is not required in splitting the water molecules to transient bubbles as in the other underwater electrical discharge system which requires voltage not less than 5 to 6KV, and very high current over 200A in pulsed supply. While pulse supply in the proposed invention is only acting as an enhancement. Plasma discharge will also take place in gas pockets or bubbles away from the electrode as long as the electric field strength is sufficient to cause such discharge.

The electrolyte also serves as a confinement of gas generated within the system, or purposely introduced gas of known properties, instead of ordinary air which may lead to production of unwanted NOx for example. Noble gas such as argon is not necessary to enhance the initiation of glow discharge sometime required in the air discharge system.

The electrolyte is also serves as a conductor and passage for the transportation of ionized species and transmission of electrons. The ionized atoms and molecules deriving from the electrolyte will be collected in their respective electrodes in the form of gas or material deposit. These ionized species are either serving as a reduction or oxidation agent in their respective half-cell. Since the gas ions produced during the discharge migrate to their respective poles to be collected individually. Hydrogen gas and oxygen gas can be collected separately.

The gas and vapor molecules and atoms inside the bubble which undergo plasma glow discharge are ionized, excited or dissociated to produce the very active species for reduction, oxidation, and the forming of neutral or radical species

which in turn react with the chemical elements present in the gas and liquid interface aligning bubbles wall. The shear number of bubbles generated near the electrodes and in the liquid comes into contact with a much larger volume of liquid that provides effective treatment, breakdown, transformation of chemicals, organic matter or elements which have been targeted.

Liquid is a good media for transmitting ultrasonic waves. Sonic-excitation is beneficial for the dissociation of materials and extermination of microbes and aids the breakdown and local melting of colloidal solids during impact which also enhances the plasma oxide reduction process. The generated ultrasonic cavitations may be fully utilized to work in conjunction with the under liquid plasma discharge. An ultrasonic cavity is micro in size and uniformly distributed in the entire liquid volume. The cavities are highly vacuum which contain liquid vapor and gas, which favor plasma discharge. The high temperature and pressure reaching 10, OOOK and thousand of atmospheric pressure produced on the collapsing phase of these cavities work is complementary to that of the electro discharge plasma. This enables under-liquid plasma. discharge to spread further from the electrodes and well distributed in the liquid volume to increase its over all effectiveness.

The electrolyte may also be in the form of mixture, emulsified liquid, colloid, foams encapsulating gas emission deriving from the liquid or introduced externally. The emulsified liquid of oil water mixture and encapsulating gas of hydrocarbon fuel with the ultrasonic irradiation will facilitate their reformation for hydrogen production.

Fine granular insoluble particles of mineral oxide such as aluminium, titanium, iron, silica etc. can be suspended in the form of colloid with the liquid which is than subjected to reduction with active ionic hydrogen atoms in a highly reactive plasma catalytic environment to become deoxidized and refined. This will be more so with the assistance of sonic impedance. The Plasma glow discharge has also demonstrated the ability to dissociate soluble ionic metal compounds, whereby subsequently the positively charged metal ions will be segregated near or by cathode electrode in the form of precipitation and plasma electroplating deposition.

The electrolyte may be a source of materials for thin film deposition with the assistance of plasma glow discharge. In addition nano size particles of certain compounds and elements i. e. Metal hydride, oxide, pure metals, semi metals, organic, ceramic etc can also be produced with the assistance of the under liquid plasma discharge in conjunction with ultrasonic cavitations mechanism to cause breakdown and reformation'of certain compound. The highly catalytic, reactive and dissociation capacity of the glow discharge plasma reforms and reconstitutes chemical elements and compounds from basic atoms or molecules to form nano particles. These include organic, inorganic, metallic and non-metallic materials such as silica, titanium carbon and etc. This is also a very effective way to extract or remove heavy metals from liquid by oxidizing such as Hg to HgO; Cu, Zn, Cr and etc. to form hydroxide precipitation and ionic metal solute to be deposited by the plasma electroplating process.

The under liquid plasma creates a highly catalytic and reactive environment for chemical reactions which would not take place under normal circumstances. The reductive species i. e. H+ and oxidative radicals i. e. O-, 03, H202, OH-and other radical species produced in the electrolysis and plasma dissociation derived from the liquid itself. The sonic excitation action that enhances the effectiveness of plasma discharge can only be conducted spontaneously under and within liquid.

The under liquid plasma technique coupled with the sonic-excitation and electro- chemical action creates an environment of localized high temperature up to 10, 000K and pressure up to thousands of atmospheric pressure that favor the generation of cold fusion phenomena.

It is a low energy system. Generally high voltage from 0.35KV up to 3KV with low current density rarely required more than 3Amp/cm2 will be needed to deal with a vast number of different types of the under liquid plasma process. If other enhancement method is applied the high voltage and current requirement will be further reduced.

It is a method for producing hydrogen, oxygen with water or other gases and material deposition with liquid containing chemical solute, other than the conventional exchange of ions. The molecules and atoms are being ionized,

excited and subjected to dissociation to form ionized, radicals and neutral species by the influence of plasma discharge. The dissociated species can be produced near either anode or cathode electrodes. The ionized species are then attracted to their respective polarity to be neutralized to produce gas or deposition of materials. The dissociation of atoms or molecules are the result of electron collisions and a wide variety of dissociated species is produced which creates the reactive elements for reduction, oxidation, and highly catalytic environments that facilitate chemical reaction of those relatively stable compounds and elements.

- No chemicals are needed as an additive in a decontamination process, of which chemicals, i. e. chlorine and ozone, could become a secondary source of pollution.

Experimental Observations When sufficient micro bubbles originating from the electrode surface block the current flow, the voltage rises steadily until a point of voltage inception is reached whereby some micro bubbles begin experiencing glow discharge. This precurs an avalanche effect which spreads through other micro bubbles close by.

A massive light is then emitted in a flash with a sound of bursting bubbles. The light is yellow to orange colour indicating plasma discharge in hydrogen gas at the cathode electrode. Before long after switching on the reactor, temperature in the electrode rises which contributes to the formation of vapour bubbles which creates a large bubble environment full of water vapor whereby the next succession of plasma discharge takes place within fraction of seconds.

The features which enable the trapping of gas, concentration of current density within a small region, continue replenishment of gas, steady and self regulating voltage and current power supply, electrode spacing, electrode configuration and electrolyte concentration all having bearing to generate desirable steady and short cycle plasma glow discharge.

Based on the above mentioned advantages and experimental observation of plasma glow discharge generated within or under liquid at one atmospheric pressure by utilizing the present invention, the present invention has a number of utilities including: - Plasma assisted electrolysis for hydrogen generation.

- Non-thermal plasma reformation of hydrocarbon and hydrogen rich compound for the production of hydrogen.

- Treatment of polluted and contaminated liquid waste containing chemical and heavy metal pollutants.

- Treatment of polluted gas emission and removal of odour.

- Sterilization of drinking water and liquid food.

- Extraction and refinement of mineral from its oxide or oxide ores.

- Production of nano particles.

- Enhancement of material's chemical and physical properties by plasma discharge irradiation under liquid condition. This also favours the need of any plasma reaction and treatment under liquid.

The invention will now be described by way of a detailed description of preferred embodiments whereby reference is made to the figures wherein; Fig. 1 is a schematic sectional front view of apparatus for carrying out a method in accordance with the invention; Fig. 2 is a schematic sectional front view of a variation on the apparatus of Fig.

1; Fig. 3 is a schematic sectional-front view of an apparatus in accordance with the invention suitable for producing hydrogen gas ; Fig. 4 is a schematic sectional front view of a tubular reactor carrying out a method in accordance with another embodiment of the invention;

Fig. 5 is a schematic flow sheet of apparatus in the form of a cell for carrying out the invention; Fig. 6 is a schematic view of a bath for the cell of Fig. 5 having an ultrasonic generator for generating bubbles; Fig. 7 is a schematic graph of current against voltage in an electrolytic cell ; Fig. 8 shows the initial formation of a bubble sheath around the cathode due to the application of voltage across the electrodes ; and Fig. 9 shows the bubble sheath around the cathode during stable glow discharge within the cell.

Figures 10-105 refer to further embodiments and experimental results in respect of the present invention.

Fig. 1 illustrates a basic apparatus 1 for carrying out the method of the invention, namely generating a plasma within bubbles formed adjacent a cathode within-an aqueous medium.

The apparatus 1 comprises a liquid containment means in the form of an open rectangular tank 2 opening to the atmosphere and containing an aqueous liquid 3. A stirrer 4 for agitating the aqueous liquid projects into the tank 2.

Two spaced cathodes 5 are positioned in the tank 2 alternating with three anodes 6 projecting into the tank 2 and extending generally parallel to'the cathodes 5. A bubble pipe 8 is positioned at the bottom of the tank 2 for introducing bubbles into the aqueous medium in proximity to each of the cathodes 5.

The application of a suitable'potential difference across the anodes and cathodes leads to a glow discharge being formed and a plasma within the bubbles adjacent the cathode. This ionises the atoms and/or molecules within the bubbles and can be used to achieve a number of industrially and commercially useful objectives.

For example it can be used to generate hydrogen gas, one of its use is in a fuel cell to generate electricity. It can also be used to neutralise harmful compounds within the aqueous medium, e. g. originating in a liquid source or a contaminated gas and treating these harmful compounds. Finally it can also be used to coat the surface of an article with a particular material.

Each of the cathodes is in the form of a perforated tube. At least one end of the tube is open and typically gas is introduced through such an open end. The side

wall of the tube is perforated such that gas issues from the tube into the aqueous medium around the cathode. By contrast each of the anodes may be rod-like.

Fig. 2 illustrates a variation on the apparatus of Fig. 1. This description will be confined to the difference between the Fig. 1 and Fig. 2 apparatuses.

In Fig. 2 the electrodes extend horizontally with each cathode positioned between two vertically spaced anodes.

Fig. 3 illustrates an apparatus suitable for the generation of hydrogen. The tank contains an anode and a cathode spaced apart from each other. The electrodes are generally the same as those described above with reference to Fig. 1. The cathode is surrounded by a semi-permeable membrane. Specifically the membrane is designed to resist the passage of hydrogen and oxygen bubbles therethrough.

Hydrogen gas is formed from the combining the two neutralized hydrogen ions adjacent to the cathode and then is drawn off the aqueous medium above the cathode and collected for use.

Similarly oxygen gas is formed adjacent to the anode and this is also drawn off separately and collected for use.

An advantage of this method for the formation of hydrogen fuel is that it consumes essentially less energy than other known methods and as a result will be a very attractive source of hydrogen for use in fuel cells.

Fig. 4 illustrates a tubular reactor which is quite different to the tank 2 shown in the previous embodiment.

The reactor 30 comprises a circular cylindrical body 31 with its longitudinal axis extending in a horizontally extending fashion. A pair of electrodes 32,33 extend longitudinally through the body spaced in from the wall of the body 31. Each cathode 33 is formed by a perforated tube. By contrast the anode is formed by the body 31.

Thus the single anode 31 extends concentrically around the cathodes 33, radially inwardly therefrom. A gas which ultimately forms the bubbles is pumped into the cathodes, e. g. through open ends thereof and then issues through the opens defined in the cathodes 33 along their length.

Settling tanks are located at each end of the body 31. The settling tanks 40 permit gas to be separated from liquid. The gas rises to the top of the tanks 40 from where it can be drawn off. The aqueous liquid can be drawn off through a drain point positioned below this level of aqueous medium in the tank 40. Aqueous medium can

also be introduced into the apparatus generally by passing it through an inlet into one of the tanks 40.

Otherwise the method of generating plasma in bubbles adjacent to the cathodes is very similar to that described above with reference to Figures 1 to 3.

In Fig. 5 reference numeral 1 refers generally to apparatus in the form of a cell and associated components for carrying out a plasma electroplating process (PEP) in accordance with the invention.

The cell 1 comprises broadly a liquid containment means in the form of a bath which is filled with an electrolyte which also forms part of the apparatus or cell.

A pair of spaced electrodes are positioned in the bath, one being a cathode and the other being an anode.

An electrical circuit is formed by electrically connecting. up the anode and cathode to a power supply, e. g. a mains power supply. When the bath is being used a potential difference is applied across the electrodes.

A partition divides the bath into an electrode compartment and a circulating compartment. Electrolyte is drawn off the circulating compartment and pumped through a heat exchanger to cool it and then return it to the bath. This helps to keep the temperature of the electrolyte within a suitable range during operation. In addition a make up tank is positioned adjacent the circulating compartment to replenish the level of electrolyte within the bath as and when required.

The apparatus also includes means for producing a bubble sheath around the cathode. The bubbles can be generated by gas evolved at the cathode as a result of a cathodic electrochemical reaction. This is one of the ways in which the bubbles were generated in the experiments conducted by the applicant.

There are however alternative ways of generating the bubbles for the bubble sheath. One alternative way is by boiling the solution (ebullition bubbles). Other ways of producing the bubbles are by cavitation generated by ultrasonic waves or by hydrodynamic flow. Entrainment bubbles can also be produced by a mixture of gas and liquids.

Fig. 6 illustrates an ultrasonic generator surrounding a bath similar to that in Fig. 5. The generator generates ultrasonic waves which are transmitted into the electrolyte liquid and act to generate bubbles in the electrolyte which then surround the cathode.

The cathode which typically provides the surface for deposition can be formed of a conductive material, a semi-conductive material or a non-conductive material, coated with a conductive coating. Cathodic materials that have been successfully used in this method are nickel, mild steel, stainless steel, tungsten and aluminium.

The cathode can be in the form of either a plate, a mesh, a rod or wire. There may be any number of cathodes and the cathodes can be any shape or size.

Any conductive material can be used for the anodes. Graphite, aluminium and stainless steel have all been successfully used to practise this method by the applicant. Generally aluminium is preferred for the anodes. There may be any number of anodes and the anodes can be any shape.

In use the bath is filled with an appropriate electrolyte. The electrolyte contains broadly a solvent or carrier which provides a liquid environment within which electrolysis can occur and which also provides a support for plasma generation in the sense that it provides containment-forthe piasma generation. The electrolyte also contains a source of the material-to be deposited in the form of a precursor. The electrolyte may also include additives for example for enhancing the electrical conductivity of the electrolyte and also for assisting in bubble formation and a buffer to maintain a suitable pH in the cell.

In use the article to be coated is placed in the bath where it typically forms the cathode. In some instances however it may also form the anode.

A voltage or potential difference is then. applied across the electrodes and this voltage is set at a level that is higher than the firing point at which'the system or cell achieves a stable glow discharge in which glow clusters envelope the cathode surface.

Fig. 7 illustrates a typical current against voltage profile for such a cell as the voltage is progressively increased. Initially there is an ohmic zone where the current increases proportionally with the voltage. After that the curve enters an oscillation zone where the current starts to oscillate. Applicant believes that this condition may be due to the fact that bubbles are evolving out of the solution and partly obscuring the electrodes. The bubbles form plasma, grow and then burst forming a shield shrouding the electrode. These bubbles block the conducting part of the cathode and this might lead to a decrease in apparent current density.

At the cathode the evolved bubbles include hydrogen generated by the electrolysis of water in the electrolyte and also by evaporation of liquid within the electrolyte. The bubbles may also be generated by other means as described above, for example ultrasonic generation.

After some time the number and density of bubbles increases until the entire cathode surface is sheathed in bubbles. At a critical voltage that is constant for a given system, known as the fire point, a glow discharge is formed. Experimental observation shows that this occurs when there is a near continuous bubble sheath around the cathode.

With a wire cathode, a tiny fireball or cluster of fireballs usually appears at the tip of the wire at the fire point. With further increases in voltage a glow discharge is established across the entire cathode. The glow discharge is dynamic and usually shows evidence of glow clusters and/or flashing through the bubble region.

The glow discharge is caused by a dielectric breakdown in the bubbles. This is caused mainly by a high electrical field strength. Due to the presence of the bubbles the majority of the voltage drop from the anode to the cathode occurs in the near cathode region occupied by the bubbles. The electric field strength in this region may be of the order of 1x104 to 1x105V/m.

The voltage is set at a setting of 50 to 100 volts higher than the ignition point.

This may typically mean a setting of 250 to 1500 volts. A preferred voltage setting would be at the low point of the graph in Fig. 4 within the glow discharge region.

The glow discharge causes the generation of a plasma in the bubble. Fig. 8 shows the formation of a bubble sheath around the cathode. Fig. 9 shows the cathode during stable glow discharge. As shown in the drawings, applicant has observed the formation of two distinct zones during stable glow discharge.

In zone 1 where the glow discharge clusters are present there is a plasma envelope that directly shrouds the cathode surface. This envelope is where plasma deposition takes place. The plasma interacts with the cathode surface in a process similar to ion plating and deposition occurs. A film is progressively formed through nucleation and growth on the cathode surface.

Zone 2 is a plasma-chemical reaction zone which forms the interface between the electrolyte and zone 1. This zone envelopes the plasma deposition zone and is often clearly visible as a separate region with a milky appearance.

Dissociation and possibly also ionisation of the electrolyte components, including the precursor, occur in the outer zone or zone 2. This gives rise to the species that are deposited on the cathode. The species is transferred from the outer zone 2 to the inner zone 1 by the electric field strength, diffusion, and convection.

Deposition on the cathode then occurs for as long as these conditions are maintained and the precursor material is available in the electrolyte.

After the glow discharge commences the temperature of the electrodes increases in a short space of time. The temperature of the electrolyte must be maintained within acceptable limits for certain type of application. To do this electrolyte is drawn off from the bath and pumped through a cooling system as shown in Fig. 5. The cooled electrolyte is then re-introduced back into the bath. This cooling is required for both stability and safety reasons. Some of the electrolyte components are flammable. In addition electrolyte is consumed during the deposition reaction. Accordingly it is necessary to replenish the bath with make up amounts of electrolyte from time to time. A replenishment tank containing electrolytes is provided to perform this purpose.

A further advantage of the method described above is that plasma can be generated with relative ease within bubbles in the aqueous medium. It does not require excessive amounts of energy and also can be done at atmospheric pressure.

It certainly does not require a vacuum chamber.

A further advantage of the invention is that it provides a method of treating aqueous waste that removed components that cannot be neutralised or otherwise rendered harmful by the addition of chemicals to the liquid.

As referred to above, a reactor cell, according to the present invention, Fig.

10, consists of a pair of metal electrodes spaced apart and separated by an ion- conducting diaphragm.

Alternatively the reactor may also consist of multiple pairs of electrodes with anodes and cathodes alternatively placed with a diaphragm in between Fig. 11.

The electrodes can also be positioned horizontally or vertically.

The diaphragm can be removed for decontamination and partial oxidation reformation process (Fig. 12). In the case of reduction process, the hydrogen atoms produced on the side of cathode electrode are kept well separated from mixing back

with oxygen by a diaphragm (Fig. 13) It is possible to increase the through put capacity of the reactor in treating contaminants with transverse flow through multitudes of alternating electrodes of anode and cathode (Fig. 14). Wires or rods in tube reactors are suitable to adopt for hydrogen production and reduction process with the metal oxide confined within the narrow space within the cathode half cell and subjecting it to ultrasonic'irradiation (Figures 15 and 16). Tube in tube reactor (Fig.

17) has a tube electrode within the outer tube electrode instead of wire or rod. The inner tube is covered with non conductive materials of suitable thickness with small diameter holes and gas trap forming in between the inner metal tube which also have small holes formed correspondingly. The gap between the outer electrode and inner electrode is kept close but giving a minimum 3mm to 5mm-space between the separation diaphragm and the dielectric cover of the inner electrode, to allow free flow of electrolyte and gas. Bubbles of gas will be discharge in to the plasma discharging zone with hydrocarbon rich gas i. e. methane, natural-gas, H2S to undergo reformation for the production of hydrogen gas. It can aiso be adopted for decontamination of polluted gas laden with NOx, SOx and particulates ; and reduction process where the metal oxide will flow through the space between the electrodes with the ultrasonic irradiation keeping the fine powder in colloidal and at the same time hydrogen gas or methane gas may also bubble in to provide the extra H2, H+ and CO to enhance the reduction process.

A number of gas trap and bubble retaining arrangements figures 18 a-f are shown.

The under liquid plasma discharge in order to produce various reductive, oxidative, radicals and neutrals species through excitation, ionization and dissociation of the liquid'molecules and atoms require high voltage input DC or AC, normally within 3KV and current density under 3Amp/cm2. The electrodes cathode and anode has to kept close as far as possible but not too close to avoid arcing. The electrode surface is preferably evenly flat and smooth without pronounce irregularity. Because of the need of placing diaphragm and complementary gas trapping and retaining construction on the discharging electrode a minimum distance of 6mm to 15mm has been experimented to produce steady glow plasma under liquid. With better material choice and engineering capability there is no reason why the electrode space distant

can not be further reduced. The sizes, shapes and arrangement of the electrodes are not restricted. But usually its size will comparatively smaller than that require for the conventional electrolysis for the same gas production volume. Both the electrodes anode and cathode can be work in the same time as plasma discharging electrode especially gas trapping dielectric cover construction is provided.

Experiments have been conducted to establish the basic criteria to generate steady and rapid cyclical non thermal plasma glow discharge under liquid with basic DC high voltage and low current input at atmospheric pressure and ambient temperature leading to the proposal of a phenomenal model of reactor structure and electrode configuration which demonstrate the usefulness of bubbles or gas pocket that creates the under liquid environment for plasma discharge and it also provides the back ground of further improvement and construction of reactor unite which verify the inventive idea of under liquid plasma and it subsequent practical applications.

The design and configuration of the electrodes is the resuit of numerous investigations on how to produce steady plasma discharge under liquid. The reactor and electrode configuration can be positioned vertically or horizontally. However this is only serves as a demonstration that steady plasma can be generated under liquid and it is not to exclude other possible reactor designs and electrode configurations which satisfy those fundamental physical and chemical criteria already well described in the foregoing text especially when other enhancement technique is introduced to the reaction process such as ultrasonic irritation, RF, microwaves, laser, magnetron field and pulsed power input.

A reactor according to the present invention can basically follow that of a simple water electrolysis cell with one anode electrode separated from the cathode electrode with an ion conducting membrane and yet has the capability to prevent remixing of the produced gas on each half-cell. The electrolyte allows moving across the membrane or replenish through the opening in the reactor. In order to increase the proficiency of the reactor the cathode electrode is placed in between two-anode electrode and separated by a membrane. The hydrogen gas produced is isolated and collected independently. The polarity of the electrode can be reverted with anode electrode in the middle when oxidative species are needed for the decontamination process. Most importantly the simple electrode and reactor unite will form the basic

module, placed inside a common bath and linked to become a major production unite, which can be individually replaced.

Despite the apparent success of the simple perforated plate to plate electrode arrangement, it does not preclude the usefulness of other electrode configuration and arrangement such as tube in tube, wire in tube and other flat surface electrodes having different surface structure e. g. wire mesh, expanded metals, pinned plate, sponge porous metal, corrugated plate and etc. as long as it is a good electric conductor, corrosion resistant, heat tolerance materials i. e. stainless steel, aluminium, graphite, platinum and etc.. The shape and size of the electrode piece is not restricted and sometime it may form the-object article to undergo plasma surface enhancement treatment.

In practice a reactor with vertical electrodes suits plasma assisted water electrolysis, reformation of hydro-carbon liquid fuel, production of nano materials and decontamination process, while the reactor with horizontally position electrodes suit reformation of hydro-carbon gas such as natural gas, methane, hydrogen sulphurs and the like.

The developed ability in generating steady plasma discharge can well be adopted for other useful purposes such as thin and thick film deposition and additional method in the creating of cold fusion.

There have been a series of experiments'conducted to provide proves to generate non-thermal plasma under liquid by utilizing the gas bubbles self generated during electrolysis, electrochemical reaction, heating and releasing of dissolved air or gases in the liquid. Bubbles can also be produce with the influence such as transient bubbles created by shock waves resulted from pulsed power input, ultrasonic cavitations, laser heating and hydraulic impingement. External introduced gas (eg. air & fuel gas) is found to work well in providing bubbles environment for ready plasma discharge in a steady manner. A number of experiments have also been conducted to test the applicability of under liquid plasma in the field of hydrogen generation, hydrocarbon fuel reformation, sterilization and decontamination and reduction of metal oxide. Because of the restriction of the power converter that some result is less than ideal but it all indicate the potential of the under liquid plasma which is in the first place having the same physical/chemical capability as its counter part operating in

gases environment in exciting, ionization and dissociation, but with some distinctive advantage which has well. been described in the foregoing text.

Generation of steady plasma discharge under liquid has been one of the primary objectives in the research. In general the generation of steady plasma glow discharge are influenced by a number of factors, such as physical and chemical properties of the liquid, its conductivity, temperature, electrode type, electrode spacing, gas retaining or trapping arrangement, current density, voltage input, reactor construction, liquid circulation, influence of ultrasonic irradiation, pulsed power input and etc.

There are of course a number of electrode shapes, size and configuration one could choose. In order to find out the how important is the supply of bubbles or gas pocket affects the generation of plasma, a gas retaining or trapping covering with current concentrating conducting holes over perforated plate electrode is formulated, which has proved effective producing steady glow plasma discharge within the range of 350V to 2KV (2000V) and current up to 850mA, but most the time around 100 to 300 mA range. This is considered low in compare with other under liquid plasma system (i. e. Plasma arc, pulsed high voltage and current electric discharge).

Throughout the experiments, a horizontal reactor was used. However an alternative reactor is a vertical reactor.

Construction of horizontal reactor and its application : The horizontal reactor (Fig. 19) is constructed of perplex glass for its transparency and easy engineering. The reactor comprises a gas outlet 1, a gas outlet chamber 2, a bottom plate of reactor 4, a spacer footing 5, drilled holes 6 in the perforated cover plate, an anode 7 electrode, a separating membrane 8, a perforated plate 9, a hollowed plastic plate 10, bolting 11, a holding plate 12 to electrode, a heat couple insert 13, an electricity conductor 14, a cathode electrode 15, holes for returning liquid 16, top of reactor 17, and a gas trapping chamber 18 formed by a hollowed plastic plate 10.

The reactor has external size of 120x90x60 mm. The electrode consists of perforated stainless steel sheet about 0.5mm thick. The discharging electrode (15) is on the top part of the reactor and is bonded to a hollowed plastic plate (18) of 2mm

thick. Another perforated plastic plate of 5 to 6mm thick (6) with drilled holes is bonded to the underside of the hollowed plastic plate (18). They become an electrode with gas traps and current concentrating holes where plasma discharge would occur.

The other perforated electrode (7) is placed at the bottom of the reactor separated by a ion conducting membrane which will keep the gas generated in the lower electrode separated. The lower perforated electrode and membrane do allow entrance and replenishment of electrolyte into the reaction zone. in general the upper electrode is cathode, which produce hydrogen during electrolysis, and the lower electrode is the anode with membrane separating oxygen produced. The upper electrode can be used, as anode when oxidative species are needed catalytic oxidation process. The produced hydrogen is collected through the gas chamber (2&3), which is connected, to the gas-trapping chamber (18) through horizontal holes formed in (10). The collected gas will be piped through a gas liquid separator and water cool chilling column to remove much of the gas vapor. The dry and cooled gas will be piping through a wet type voiume-measuring meter or through a chromatogram for analysis.

The electrode gap distance between the two electrodes will be adjusted by using different thickness of the gas trapping plate (10), and perforated plate (9).

An exploded view of a reactor according to the present invention is shown in Fig. 20, wherein: 1: bolting ; 2: top plate ; 3: sealing plate ; 4: cathode; 5: hollowed plastic plate to form gas trap; 6: perforated plate ; 7: spacer plate ; 8,10 : another membrane for anode; 11: anode; 12: bottom plate of reactor.

A perforated discharging electrode (cathode) 35mm x 30mm according to the present invention is shown in Fig. 21.

The size of perforated (cathode) discharging plate electrode is smaller than the other (anode) perforated electrode of size 60mm x 65mm.

The perforated perplex covering plate serving as current concentrator is having thickness of 3 to 6 mm. The number and diameter of holes to be adjusted in accordance with the physical/chemical properties of the electrolytic liquid and its conductivity. The diameter of the hole varies from 1.0 to 2.0 mm.

A perforated cover plastic plate according to the present invention is shown in Fig. 22.

In the experimental reactor, perforated cover plate with 80 holes of 1. Omm dia or 2. 0mm dia have been adopted. This cover plate is securely bonded to the hollow plastic (gas trapping plate) which in turn bonded to the discharging electrode. The bonding should be air tight to prevent bubbles escaping to the side. Various component part of the reactor are bolted tight together making sure all produced gas in the reaction zone is collected through the gas chamber.

The working principle of the horizontal rector The reactor is submerged in an electrolytic bath. Gas is produced by electrolysis on passing of electricity. The gas produced at the (cathode) discharging electrode is being retained in the gas trapping hollow and gradually build up shrouding the entire electrode-forming a dielectric barrier. The current between the two electrodes is high at the beginning but will be gradually lowered due to the present of bubbles. Some of the gas may also enter the perforated holes in the cover plate. The voltage rises quickly and current falls correspondingly. An inception voltage is reached with sporadic infrequent light spots resembling a corona discharge. When the voltage increased further a more steady extensive and frequent illumination of yellowish red color is observed which is believed to be plasma glow discharge. The discharge will mostly take place inside the perforated holes where there are gas bubbles and at the region of high current density (see photo A&B). The temperature measured at the discharging electrode and liquid is relatively low in the range of 50°C but gradually increased to about 90°C at the electrode and about 70°C in the liquid. The plasma discharge is considered non-thermal which is taking place under liquid and at one atmospheric pressure. When the voltage allow to increase, plasma arc occurs with bight blue color covering an extended surface of the reactor The high temperature produced by plasma arc will damage the reactor if it allow to happen for short time.

When the dielectric bubbles barrier is experiencing plasma discharge or electric break down, the current will increase immediately. In the same time, the plasma discharge causes dissociation of vapor molecules contain inside the bubbles and those aligning the bubble wall with will produce additional gas which enlarge the

bubble or existing gas volume. Some of the gas will be expelled to outside through the perforated holes which will be collected in the gas chamber and piped out. The bubble continue to formed by electrolysis, plasma dissociation and more important by heating as reaction continued. The formation of bubbles, plasma discharge, expelled, replenishment will be in a continue cycle. The plasma discharge is gradually settled to a more steady and rapid cyclical manner that the voltage is found to be nearly stationary at high level and the current is lowered but fluctuating. The under liquid plasma discharge is over ally considered a dynamically equilibrium reaction system.

Construction of vertical reactor A reactor according to the present invention can also be constructed with the electrodes placed vertically demonstrated in the diagram. The electrodes are separated by a diaphragm and discharging electrode (cathode) which is placed in between two outer electrodes (anode). The discharging electrode is bonded on both sides with the gas trapping and current concentrating covering construction similar to that of the horizontal reactor. The only different is that the gas trapping chamber instead of one continue gap spacing is now separated by individual pocket to retain the gas locally and stopping it all float to the top. The polarity of the discharging electrode can be reverted from cathode to anode if so required.

The mechanism of plasma discharge is very similar to that of the horizontal reactor. However it has the advantage to allow the generated gas rising quickly to top and will reduced the amount of recombination of dissociated elements reverting back to their former composition such as the case of H and OH reverting back to water.

A vertical reactor according to the present invention is shown in Fig. 23, wherein: 1: diaphragm; 2: perforated covering plate ; 3: anode; 4: holes in the reactor wall ; 5: bottom plate of the reactor ; 6: gas trapping chamber; 7: cathode ; 8: cover plate of reactor; 9: void space inside reactor; 10: gas outlet ; 11: entrance for heat couple.

Introduction to the experiments Several groups of experiments have been conducted: 1. Preliminary trial experiments 2. Plasma assisted water electrolysis 3. Reformation of methanol 4. Reformation of emulsified diesel 5. Reformation of LPG as hydrocarbon gas (methane is not available in the market) 6. Decontamination or sterilization of food drink 7. Reduction experiment of Ti02.

In the preliminary trial experiments a number of electrode types have been adopted and have eventually select the wire to plate configuration and perforated plate to perforated plate or wire mesh as the most suitable under the limiting power supply condition where max. voltage available is 2000V and the max. current is 1200mA. In reality the current input is voluntarily restricted to work below 900mA for duration not exceeding 30 minutes to avoid damage to the converter which has happen in a number of occasion which caused stoppage of the experiments for weeks.

To overcome the power supply limitation and to achieve steady plasma glow discharge, a gas retaining or trapping cover or layer with current concentration holes has been devised to cover the discharging electrode surface (perforated electrode plate) which is the basic features adopted in the construction of reactor.

In the trial experiments, it has demonstrated that infrequent visual plasma discharge begins with voltage of 350V and steady plasma can be achieved in around 550V. The initial current input reaches 850 mA and began to fluctuating in the range of 150 to 650 mA. In many occasion the current fluctuated at 1 OOmA to 350mA.

Through these experiments the mechanism of generating bubbles or gas pocket dielectric barrier which impede the current flow leading to increase of voltage until an inception voltage is reached and cause the electric break down in the

formation of plasma inside the bubble and the current immediately return to its normal flow and subsequently impeded for another cycle of discharge is established.

When the discharge is infrequent which resemble corona streamer discharge. But as the voltage increases the glow discharge is becoming a continued glow over an extend electrode surface resembling a glow plasma discharge. The color of the discharge appears in orange yellow or red color in the electrolysis of water and the temperature of the discharging electrode is ranging from 50 to about 90°C and the temperature of the bath liquid is ranging from 40 to 70°C. No sign of any damage to the electrode or its covering plastic gas trapping plate after prolong experiment.

When the voltage allow to increase beyond the glow plasma region, plasma arc begin to occurs and become intensive bright blue discharge when voltage further increased and damage to the metal electrode and plastic covering plate are obvious.

In two occasions hydrogen production is recorded to produce in quantity with equivalent energy conversion efficiency up to 56%. Due to damage to the reactor by plasma arc that the experiment cannot repeat with a different model of reactor which is designed to achieve low current input and early high voltage response. However with the apparent success of the trial experiment that a more suitable reactor can be designed specifically for the purpose of hydrogen production for the plasma assisted water electrolysis and higher energy efficiency figure with small reactor can be developed.

Plasma Assisted Water Electrolysis Experiments, the behavior of plasma discharge at different voltage input is investigated. Despite of the apparent bubbles boiling inside the reactor the total volume of gas produced is unexpectedly low.

This may have been attributed to the horizontal reactor adopted through out the experiments that allow the produced hydrogen gas to recombine with the hydroxyl ions back to water. Vertical reactor would be more suited for the plasma assisted water electrolysis where the produced hydrogen gas will rise quickly to top of reactor and can also channel away from the area abounded with OH ions.

In this experiments plasma discharge begin to occur at 1350V with current fluctuating around 100 to 200mA. At about 1550V the reactor produced highest

volume of gas. Plasma arc discharge occurs at 1900V and is becoming vigorous when the voltage is increased further. KOH of 0.02% concentration has been used as electrolyte additive through out the experiment.

The production of gas appears to have a linear relation with time but various substantially with different voltage input. The rate of energy consumption is increasing slowly with time in a constant rate which various with the voltage input and its corresponding energy consumption per unit gas volume produced is having a peak at the first 10 minutes of the experiments and level off with time. The temperature in the electrode rise sharply to from 50°C to 90°C and is also maintain more or less at that level through out the test. The temperature in the bath liquid within the reactor rises slowly from its ambient temperature at around 50 to 55°C.

Experiments with methanol There are several sets of test have been conducted with the aim to find out how different hydro-carbon fuel will be affected by the non-thermal plasma under liquid. Methanol water mixture with methanol concentration ranging from 5%, 10%, 15%, 20%, 25%, 30% and 40% are tested with method and equipment set up similar to that of plasma assisted water electrolysis. There are three independent tests to each methanol concentration. It has been observed that the gas production is peaked at 25% methanol concentration and the energy consumption per unit gas volume produced is also lower than the others and is nearly at constant rate around 0.0225 Kw. h/L. The voltage input for each test is kept at 1850C and the current fluctuating in the range of 100 to 200mA. ~The temperature measured at the cathode electrode starts at 80°C and rise quickly to reach over 200°C at the end of 30 minutes experiment. The temperature recorded in other test stay within the range of 60 to 80°C. The temperature of bath liquid at 25% concentration stays in the range of 50 to 60°C, which is in average with the others.

The greatest surprise coming out of the experiments is that the produced gas is composing of two gases. One is hydrogen gas and the other is oxygen gas and no trace of carbon dioxide is found. Repeated examination of the gases produced shows the same result and the hydrogen is having an average value of 51.3% and oxygen 48.7%. This is later found out that the present of oxygen in the gas is the result of removal of separating diaphragm. Acidic electrolyte is more preferable as conducting

reagent in order to increase hydrogen gas percentage in the produced gas. This is testified in the latest experiments using sulphuric acid of 0.02% concentration.

A set of experiments with the use of 40KHz ultrasonic bath having methanol concentration of 10%, 15%, 20% and 25% with the same reactor and equipment arrangement have been conducted to find out the influence of ultrasonic irradiation. It has been observed that gas production at 25% is substantially higher than the others and yet the energy consumption per unit gas volume produced is around 0.015 Kw. h/L through out the 30 minutes experiment, which is lower than that without ultrasonic irradiation.

The chromatographic analysis of the out put gas having an average value of 97.56% hydrogen and 2.4039% of carbon monoxide.

Chromatographic analysis of gas produced by reformation of methanol with ultrasonic irradiation. Methanol concentration at 25%, and conductive reagent 0.02% sulfuric acid.

Table 1 Test resident time composition gas type Min VN% First test 0.364 98.9937 H2 1.047 1.0063 CO Second test 0.364 96.7418 H2 1.047 3.2582 CO Third test 0.354 96.9719 H2 1.048 3.0281 CO Average 97.5691 H2 2.4309 CO

Experiments with LPG Decomposition of LPG by under liquid plasma has been conducted (methane or natural gas is preferred but none is available in the market). The LPG is allowed to pass through the horizontal reactor through the perforated anode plate and enter the reactor and trapped at the cathode plate where plasma is taking place at voltage 1980V and current at100 to 130 mA input. C3H8 and C4H10 are the two main components of LPG, it is expected that the volume output having been subjected to plasma dissociation should be larger than the original input volume. This is found to be so that the out put gas volume increases by about 50% %. The experiment is conducted together with ultrasonic irradiation. It is regrettable that the chromatogram is in capable to undertake analysis of the out put gas composition. The next set of experiments should be conducted with methane or natural gas so that more definitive result could be obtained. Rudimentary analysis of the produced gas has shown the present of H2, C02 and C3H6 etc.

Reformation of emulsified diesel and water with ultrasonic irradiation Decomposition of emulsified diesel with distillate water has also been carried out. Diesel oil in 25% and 50% by volume has been emulsified by adding 1.25% emulsified agent inside the ultrasonic bath. Since the diesel oil is dielectric additive of KOH is needed. The emulsified liquid is subjected to plasma discharge at voltage 1850V and current fluctuating from 100 to 200 mA for a period of 30 minutes. The temperature of the cathode electrode is increasing from 70°C to about 94°C during the experimental period. The gas volume produced 160mLwith 25% diesel and 1740mL with 50% diesel, which is substantially higher and its energy consumption is 0.1213 Kw. h/L. It is clearly indicated that gas production is proportion to the diesel contend in the emulsion. Because of the limiting power supply, the voltage at 1850V is merely adequate to produce some plasma discharge but it is far from establishing extensive vigorous plasma with higher current and voltage input, which would produce more gas.

Sterilization (decontamination) of mulberry fruit drink The ability of non-thermal plasma to decontaminate noxious chemicals and gases has already established. This experiment is conducted to find out how well the under liquid plasma may apply in the field of beverage sterilization with low level of plasma irradiation and keeping the treated liquid within an acceptable temperature.

Two litters of 15% concentrated fruit drink is placed in the bath where a horizontal reactor is submerged. The bacteria count and mold colony count is obtained before the forty minutes test. Sample of the fruit drink is extracted at 20 minutes and forty minutes. The mulberries drink is having good natural conductivity that no conductive additive is required. Apply voltage is kept at 1200V and the current fluctuated around 200mA. The temperature at the electrode is maintaining around 62°C and the bath liquid (fruit drink) is kept at around 50°C.

Table 2 The micro-organism count Time (min. ) bacteria count/ml mold colony count/ml 0 3400 37000 20 1300 17000 40 90 10 The favor and color of the fruit drink has not changed after the test. The bacteria sterilization is 97.5% and that of mold colony has been sterilized more than 99%. This has given proof that the under liquid plasma is having the same capability as those operate in gases environment.

The time for the treatment could be reduced by providing force circulation of the liquid and increasing the electrode size. Sterilization of drinking water imposes no limit on the temperature. Higher voltage input for better plasma glow discharge

spreading over larger and multiple electrodes should be able to remove all harmful chemical substance, bacteria, biological matters and microbial meeting the municipal requirement for drinking water.

Reduction of metal oxide One trial experiment to reduce Ti02 back to Titanium has been attempt with little success. In the X-ray diffraction test minor trace of titanium nitride and titanium monoxide (TiO) is found.

In the experiment only minor electrolyte of 0.05% KOH with 25% methanol added to the distillated water to increase the production of hydrogen. Applied voltage is fixed at 1850V and the current fluctuated in the range of 200 to 500V. Ultrasonic irradiation up to 40 KHz is also provided through an ultrasonic bath. Temperature recorded in the bath liquid rising from 46 to 75°C at the end of 60 minutes test. The fine TiO2 with the irradiation of ultrasonic is suspended in the bath liquid in colloidal with milky white color, which gradually become milky yellow color towards the end of experiment. The bath liquid also becomes viscous.

The X-ray refractive d value of Ti02 are: Before the experiments 3.512, 1. 892, 2.376 After the experiment two group of d value is not observed before the experiments a. 2.089, 1.480, 2.400 b. 2.400, 2.329, 2.213 This indicate a new material at the position between TiO and n-Ti3N2-x.

This experiment indicate change did happen to the Ti02, but because of the limiting voltage and current input which has not provide the intensity plasma discharge needed to effect the reduction process properly. Higher concentration of either HCI or H2SO4 should be use as reagent demonstrated in the following

chemical reaction and in the same time serving as electrolyte. The horizontal reactor is not a suitable piece of equipment to undertake such experiment; it is adopted merely for convenient. A wire in tube and tube in tube reactor would be a suitable candidate, which will keep the metal oxide expose to plasma discharge through out the experimental period. Further more hydrogen or CO gases produced during the process may be recharged back to the reactor to enhance the reaction. (Methane is a suitable gas for this type for the reduction process, as both hydrogen and CO gas will be produced to enhance the reaction). The following are the chemical formula, which suggested by transforming Ti02 to either TiC14 or TiOS04 as soluble ionic compound will facilitate its reduction with prolong exposure to active atomic hydrogen under the influence of plasma catalytic environment.

Ti02 + 4HC)- Ti04 + 2H20, TiC14 + 4H o Ti + 4HCL.

Ti02 + H2SO4 # TiO (S04) + H20, TiO (SO4) + 4H # Ti + H2SO4 + H20 Where TiC) 4 are readily produced by established process from ilmenite.

Similarly, aluminum oxide Api203 can first be transformed to AlCl3, which is soluble ionic compound, are to be extracted by electro deposition enhanced with plasma reduction and plasma electroplating process.

Al203 + 6HCI @ 2AICI3 + 3H20, 2AIC13 + 6H i 2AI + 6HCI.

In the case of electrode positive oxide such as Fe203, it can be reduced with present of ionized atomic hydrogen and present of carbon monoxide with the catalytic reactive plasma irradiation.

Fine metal oxide powder irradiated with ultrasonic waves will maintain in colloidal form allowing them to expose to the reduction agent of atomic hydrogen and or Carbon monoxide. The process of ultrasonic cavitations and collapse is also known to create extreme localized high temperature up to 10, 000K and thousands of

atmospheric pressure together with the high temperature at the impact point of the fine powder particles is all beneficiary effect to the entire reduction process.

Details of the Experiments carried out: Establishing generation of under liquid plasma Distillated water is used in the experiments with 0.05% KOH as conducting reagent. The voltage is the controlled at 1250V & 1850V. The current is raised in step of 100mA until it reaches 850mA. At the beginning the voltage remain low and gradually build up with more gas bubbles is generated. Once the reaches a certain high level the current drops immediately. The self regulating current and voltage input of the power unit automatically switch from current input control to voltage input control. At 45 second after switching on the experiment, the voltage rose to 470V and the current dropped below 500mA. From 3 min. 10 sec to 5 min 20 sec, the voltage has risen to a relatively high level while the current is kept on fluctuating. After a period of unstable voltage and current movement they become stabilized at 20 min with the characteristic high voltage and low current. At this instant prominent glow is observed at the perforated cover plate (current concentrating holes). The temperature of the cathode electrode has risen and maintain at around 70°C.

Fig. 25 shows the current fluctuating with stable 1250V voltage input with steady plasma glow discharge.

The temperature of the cathode electrode increase at fast rate at the beginning and become steady at 5 min time and rise slowly to a highest temperature about 96°C.

Observation Generating under liquid plasma In accordance to the experimental observation, it is possible to generate non- thermal plasma under liquid providing a certain condition is met to provide suitable power supply condition, electrolytic liquid, reactor and other supplementary equipments.

The design of the reactor with relative lower voltage supply and limiting power rating (restricted current input) requires special construction to trap or retain gas and at the same time to raise the current density at the discharge area. The size of gas trap or chamber should be of suitable size. If the gas trap or chamber is too big, the trapped gas is too thick which requires much higher voltage for discharge breakdown and prolong the time of each cycle of discharge. It becomes difficult to maintain rapid cyclical steady glow discharge. The perforated covering plate is also an important part of the electrode structure concentrating the current density. The thickness perforated plate and gas trapping chamber should be well controlled so that the electrode gap spacing will not be unduly widen which also influence the voltage requirement. The size and disposition of perforated holes can be determined by few trial and errors. Wide electrode spacing increase the voltage input requirement and unsuitably close electrode spacing will cause early occurrence of plasma arcing with high current surge and generation of temperature that-wiil-damage the electrodes and their attachments.

The power unit should be of adequate power rating. The electric break down depends highly on the high voltage supply. If the power rating of the converter unit is inadequate, it will easily subjected to damage during sudden high current surge upon cyclical electric breakdown. There will be no plasma discharge if the power input is not meeting requirement.

The electrolytic liquid should have suitable conductivity, not too low nor too high. Voltage can not be easily raised between two electrodes with high conductivity in the liquid and no plasma discharge would be generated without high voltage input.

The discharging electrode may be fully encapsulated inside a bubble barrier, but with high conductivity in the liquid allow the current transmitting through the bubble liquid interface which prevent raising of voltage. If the conductivity is too low, the bubble barrier is forming a complete dielectric barrier which require a much higher inception voltage to cause electric breakdown or discharge and in the same time that the passage of current is becoming too low resulting low current density which also influencing the occurrence of discharge. A much higher breakdown voltage ( discharging voltage) is in the form of electric arcing in gaseous condition will take place which is no longer considered non-thermal under liquid plasma.

Conclusions 1. Gas layer or bubbles form the dielectric barrier that provide the environment for building up the discharge voltage and gaseous space for plasma discharge to take place. High voltage and relatively low current input is characteristic of under liquid plasma.

2. With the characteristic high voltage and low current requirement, the under liquid plasma can be generated over a wide range of liquids. The electrolyte liquid can be acidic, alkaline and solution of salts. Liquid containing conducting impurities or mixture of organic compound may also serve as electrolyte such as the case of tape water and fruit drinks.

3. There are a number of factors which would affect the generating of under liquid plasma such as voltage, current density, configuration of electrodes, area of electrode-surface, electrode gap spacing, electrolytic physical and chemical properties, gas retaining and trapping arrangement, provision of plasma enhancement, ultrasonic cavitations, pulsed power supply, ambient temperature and reactor construction. This appears complicated, but the experiments undertaken have demonstrated that all the mentioned factor can be manipulated to achieve generation of stable non-thermal plasma at one atmospheric condition.

4. Plasma is the forth state of matter, it has been wide employed in the field of chemical, electronic, materials and energy industries. Plasma generated under liquid has its own intrinsic characteristics and advantages, which has already proven a useful tool to for plasma electroplating or deposition of both metallic and non-metallic materials. It will find its application in the plasma assisted water electrolysis for hydrogen production; reformation of hydrogen rich compounds or hydrocarbon fuel (gas and liquid) ; decontamination of both liquid and gas pollution discharge containing persistent harmful chemicals, dissolved heavy metals and organic and biological contaminants; sterilization of fruit drinks, portable water supply; and reduction of material oxide such as oxide ores, metal oxide as an alternative method metal refinement. It is confidence that with the proposed under liquid plasma generation and establish basic scientific information would form the bases for further

refinement leading to practical new applications put forward in the patent application.

Plasma assisted electrolysis for hydrogen production Water electrolysis is still in use for production of pure hydrogen. Its production is restricted because of it relatively low energy conversion efficiency. In order to achieve higher energy efficient, electricity voltage is to keep low to avoid energy lost through heat conversion. There are also claims that the energy efficient can be improved with improved electrode configuration, increase of reactive surface, closing the electrode gap and increasing pressure. The PEM solid electrode system is in its early development and its efficiency remains similar to that of water electrolysis system. In any case the basic principle of water electrolysis has not changed since it put to use. The electrolysis as a whole considered non-competitive with other production process by reforming hydrocarbon fuel, but it has the advantage of being a clean process producing high gas purity and C02 is not produced.

The hydrogen bubbles evolving from the electrode surface slow down with time when tiny bubbles is gradually built up and smothering on the electrode surface which are not easily to be dislodged from the electrode surface and the rate of hydrogen production reduced further as those tiny bubbles become barrier of current flow between the two electrodes.

The proposed invention is closely related to water electrolysis process but mechanism of separating hydrogen from water molecules is different. Generating non-equilibrium plasma within the bubbles that smothering on the electrodes will breakdown the dielectric barrier bubble layer to resume normal flow of current. In the same time water molecules contains in the bubbles and come in contact with plasma discharge will be dissociated to produce extra hydrogen. In addition, the vigorous plasma discharge near electrode surface will also create hydrodynamic condition, which will wash away the fine bubbles that block the current flow. The mechanism of producing hydrogen by plasma discharge is different from the conventional

electrolysis which split the ionic water molecules by electro-polarity attraction, while in the plasma discharge the water molecule is broken down as the result of electrons collision. The water molecules under the plasma discharge irradiation would loose one electron due to electron collision to yield H20 + e-> OH + H+ + e The produced hydrogen is of high purity. Ordinary portable water or rainwater with very low concentration of electrolyte can be used as the main source of material, instead of distillated water, as they contain sufficient impurity to be slightly electro- conductive.

The experiment has demonstrated that hydrogen gas can be produced with plasma glow discharge as a supplementary process to conventional method. The energy required to produce. 1 cubic meter of hydrogen with plasma glow discharge with the very rudimentary reactor has achieved an efficiency of 56% which can be further improved with better engineering, by closing the electrode gap distance, select the right concentration of electrolyte, reactor construction and better means in trapping and retaining gas near the discharge electrode.

High temperature up to 90C is recorded in the electrolyte, which increases within very short time of the reaction. This may in part due exothermic reaction of recombining H and OH to water. The excessive heat can well be utilized as secondary source of energy. The gas or vapor bubbles by heating assuming greater importance as source materials for plasma dissociation leading to the production of Hydrogen. The high purity oxygen co-produce is also a valuable by products of many applications.

Since high voltage with moderate current is needed in the plasma process, The production rate per unite area of electrode surface is high that a smaller reactor would be needed for the production of hydrogen, especially when other plasma enhancement method is employed such as ultrasonic cavitations, pulsed powers and RF input.

The gas generates by the electrolysis and heating containing water vapors that defused within the bubbles upon sufficiently high electric potential are applied, the water gas and vapor inside the bubbles are undergone plasma dissociation. The hydrogen molecules H2 would experiencing ionization and dissociation and some

would become H, H+, H3; and the water vapors some become H+, OH-, H-, O, O-, 02-, 03, H202, H02 and etc.. Some of the water molecules at the water and gas interface of the bubble wall will also be subjected to plasma dissociation to produce extra hydrogen atoms and hydroxyl radicals. The OH radicals may also react with the water molecules aligning the bubble wall *OH+OH* and become H202. As whole many radicals, reductive, oxidative and neutral are produced. The atomic H will become neutralize on gaining back the lost electron and combined with another hydrogen neutral atom to produce a stable hydrogen molecule H2.

Plasma glow discharge is much easier to generate at the side cathode electrode than anode because there are more hydrogen gas bubbles produced which is also relatively easier to initiate glow discharge when compare with oxygen gas at the anode electrode. Light spot near the anode electrode indicate that oxygen gas also undergo plasma dissociation. This would be more so if air trapping and current concentration arrangement is provided on the anode electrode.

With the extra hydrogen supply to the bubbles through plasma dissociation the bubble will be enlarged which in turn allow greater number of water molecules to be defused within the gas bubbles. During the steady plasma glow discharge the bubble dielectric barrier is removed.

There is a number establish plasma generation enhancement techniques such as application of magnetron field, steady or pulsed RF input, pulsed high voltage supply, laser, microwaves and most important of all the single or multi-frequency ultrasonic waves which can improve the operation efficiency further.

The electrodes can be fabricated to a number of different configurations and size as long as it favors and matches the electricity input for the generation of the discharge. The space between two opposite electrodes is kept to a minimum as far as it is practicable, as this will lower the high voltage requirement in the initiation of plasma. However the gap should be far enough to avoid ready occurrence of plasma arc discharge. Generally electrode gap distance is ranging from 6mm to 15mm.

The two opposite electrodes are being separated by corrosive resistant and ion conducting diaphragm which is permeable to the flow of ions, diffusion of liquid

across two half cells and yet the pores should be small enough to stop crossing and remixing of gases such as hydrogen and oxygen gas bubbles.

The electrodes could be of any conductive materials such as aluminium, stainless steel, graphite, tungsten, platinum, and palladium etc. The size of the electrode for the plasma discharge is much smaller than that required by the conventional electrolysis to produce the same quantity of gas. As the result a smaller reactor would be possible.

Sponge porous electrode will increase the reactive surface to produce electrolysis gases. In the experiment several layers of fine wire mesh has been packed tight together to mimic a sponge porous electrode plate.

Some of the basic electrode configuration is :. plate to plate ; perforated plate to perforated plate ; plate or perforated plate to wire mesh; wire mesh to wire mesh; plate to pinned plate ; dielectric coating on one or both electrodes plate or mesh or pinned plate, tube in tube and wire in tube arrangement. It is noted that electrode configuration including any lining or covering materials that help to concentrate the current density and having the ability in retaining gas around the electrode would be adopted which will help to lower the voltage and current requirement to generate steady plasma discharge.

In order to create an environment for steady and short cyclical plasma glow discharge as already mention in previous text, the electrode configuration will be so structured to retain the bubbles and concentrating the current density and yet keeping the true electrode gap distance to minimum. This achieves by creating suitable voided space either in the metal electrode or in the covering materials to retain gas and in the same time having the mechanism to concentrate the current density to a localized discharge point. This will lead to wide variety of design and choice of materials to satisfy plasma discharge requirement.

The bubble or gas trapped in the void space can only expired through the holes in the cover plate that block the flow of current leading to the increase of voltage enabling electric break down and glow plasma discharge. The current flowing between the two electrodes is some how concentrated in passing through the hole

resulting high current density in the hole, which is one of important component to cause glow discharge. The perforated plate electrode with gas retaining arrangement on both sides will rarely have glow discharge take place simultaneously as the result it allows expiration of produced hydrogen gas to leave the confine of the gas trap on the side with least pressure. In a manner similar to breathing the void space created after expiration of gas will be filled with electrolyte allowing next cycle of electrolysis, gas and vapour produced by heating and following with succession of glow plasma discharge.

The gas, liquid and glow plasma discharge form a dynamic system rendering glow discharge occurs in an unsteady cyclical manner, however more steady short cycle discharge is possible with the right balance of electrode structure and power input.

Upon the occurrence of glow discharge, the micro bubbles will react in chain reaction and collapse and fused to form large bubble which will than be forced out through the holes in the metal electrode and the cover plate. Somehow some gas will retain in the gas trap and new gas from electrolysis and local heating during plasma glow discharge replenish the lost gas quickly that block the hole where concentrated current and voltage is surging through to create another round of glow discharge in succession.

In order to avoid recombination of H+ and H2 with OH ion in reverting back to water, the hydrogen atoms after regaining its lost electrons through contacting the cathode should allow to escape quickly away from area abounded with other oxidation species and radicals. This has greatly influenced the productivity of hydrogen gas. If H+ and OH is allowed to recombined, despite of the apparent bubble boiling in the reactor very little gas can be collected and the temperature in the reactor rise quickly which could well be the exothermic effect of recombination of H+ and OH.

The hydrogen produced is to be collected in separate from the oxygen. Since the produced hydrogen gas contain a fair amount of water vapor, the hydrogen gas is collected by passing through a water chiller or other known method, so that the measured gas volume is at room temperature with minimum contend of water vapor.

The basic plasma assisted electrolysis cell or reactor can be produced in modular form which can be packed side by side and place inside a single electrolytic tank with their respective power and out put gas collected to form a major production unite. Several reactor types can be employed for the production of hydrogen. Rod or wire in tube reactor, tube in tube reactor, single or multiple cell reactors is also suitable for the plasma assisted water electrolysis. The gas retaining and current concentrating cover will be affixed on the cathode electrode facing the anode electrode. Horizontal reactor with the cathode with gas retaining cover will be placed on top of anode which is separated by a diaphragm and the hydrogen gas is allow to collect in isolation.

The introduction of ultrasonic cavitations into the electrolytic liquid will be much easier that the electrolysis bath becomes the ultrasonic bath where ultrasonic transducers can be attached to the bath externally. A mixture of sonic frequency will be used to avoid the occurrence of dead sonic zone. The introduction of sonic excitation through cavitations will enhance the production the performance of plasma- assisted electrolysis.

Pulsed high voltage supply of DC with square wave of single polarity from 5 KHz up to 100 KHz finds to be beneficiary to generate plasma with much reduced voltage.

The distinctive advantage of the under liquid plasma enables ionized species migrate to the respective half cell and electrodes which will avoid and minimize remixing of the produced hydrogen and oxygen reverting back to water and creating hazardous explosive condition. The oxygen is considered as by product which can be collected for use or it can be channeled to combustion chamber if hydrogen is used as direct fuel for combustion engine.

Water is the primary source material for hydrogen production, which is economically available and of unlimited supply. It is a completely clean source material that produce no unwanted by products.

The anode may be gradually losing its materials due to electro transportation.

But it will be a very slow process. In practice the polarity of electrodes can be reversed which reverses the materials transportation and deposition. Conductor

materials that are inert of electro chemical corrosion will be a good choice to serve as electrodes.

Chemical conductive reagent may be added to water to increase its conductivity and foaming agent to enhance generation of bubbles. The electrolyte can be of acidic or alkaline base. The concentration of the electrolyte is to be maintaining for best result. High electrolyte concentration increases liquid conductivity as well as productivity of gas bubbles but it might prevent raising voltage required for discharge as the current flow between electrode will not be inhibited by the present of bubbles : However very low concentration of electrolyte will favor dielectric break down of bubbles, as lesser current will be conducted away by liquid media in between bubbles. It has been found that either acidic or alkaline electrolyte with 0.02% concentration work extremely well in maintaining steady glow discharge with DC voltage ranging at 350 to 1800V and current 100 to 800mA.

Tap water has been used without adding any conducting reagent works unexpected well, most likely due to present of impurity and high PH, in the plasma- assisted electrolysis where steady glow discharge occurs at around 450V to 900V and current around 200mA to 350mA. The power input requirement varies in accordance to electrode spacing, electrode and reactor configuration, electrolyte concentration and the structure of gas retaining arrangement. Again other plasma assisted method such as pulsed power input and ultrasonic cavitations etc. are also help to lower the power input requirement.

The process is in general conducted at one atmospheric pressure, Increase of pressure will slow down upward movement of the bubbles and increase of boiling temperature.

Some increase in temperature in the electrolyte is not detrimental to the generation of plasma. Water vapor bubbles provide the source materials and active environment for plasma discharge. In general electrolyte temperature is well below boiling point as non thermal plasma produces little heat. The temperature sometime rises quickly in the electrolyte due to occurrence of infrequent plasma arc and exothermic in the recombination of H+ and OH-in quantity.

Several repeated experiments were conducted to prove the viability to enhance the water electrolysis with the assistance of plasma glow discharge.

Important experimental parameters were recorded such as current, voltage and time relationship from start of experiment to observe the variation with time; hydrogen gas volume produce verses time; temperature of the electrodes plate verses time. The power supply is using Del. High voltage power converter with adjustable and self regulating voltage and current supply. The voltage increase in synchronize with current application. When current input is stepping up the voltage begin to rise steadily until an inception voltage is reach which is normally within the range of 350 to 1800V. Light spot appear and spread across most of the holes in the plastic cover and the current also drops steadily until a settling current fluctuating at around 100 to 300mA and voltage ranged from 550V to 1800V. The size of electrode is 40 x 60 mm. and the electrode gap spacing is ranging from 6mm to 15mm.

The experiment were carry on for time over 30 minute to see whether steady glow discharge can be maintain for long period of time. In certain condition the voltage and current to maintain steady glow discharge remain stationary for long period of time with very little of variation. The electrode and its cover plate find to be in original condition without any sign of erosion. However if the voltage is raised over the glow discharge region (voltage over 1800V) there are more frequent vigorous discharge with occasional electric arc discharge in localized area and several hole in the plastic cover is burned. The voltage reading immediately dropped to a very low figure and current surge to its control maximum of 1200mA.

During the steady glow discharge, vigorous bubbles with yellow-orange/red color light spots are appearing all over the plastic perforation. The light spot appear wildly also on the electrode surface by increasing the voltage. On examining the electrode and plastic cover sheet no burn mark is observed. This proves that the plasma glow is non-thermal after an hour glow discharge. The temperature in the electrode plate recorded with a thermal couple is around 50 to about 90°C. The gas produce is mainly hydrogen with some water vapors, which condense quickly on cooling. The rate of hydrogen production is variable and energy conversion rate also fluctuated through out the test. This is suspected to cause by the recombination of H and OH, which is affected by the electrode and reactor structure and configuration.

Since the experiment is conducted for the purpose to demonstrate the viability to improve the productivity of hydrogen by utilizing the under liquid or water plasma, which ensure normal current flow through the barrier bubbles enabling continue electrolysis and in the same time the bubble or air pocket instead of detriment to gas production, is in effect provide the environment for glow discharge under water where further dissociation of water molecules produce large quantity of hydrogen gas.

Hydrogen can now be produced with high voltage and low current, which is again contrary to the conventional electrolysis system that small, but fast rate production is becoming possible. This has clearly demonstrated that the mechanism of producing hydrogen with plasma discharge is different from conventional water electrolysis by a number of ways. Steam and gas vapor produced due to heating of the electrodes (cathode) in short space of time are becoming an importance source of materials for plasma dissociation that also influence the productivity of hydrogen.

Experiments and Results Under liquid plasma assisted water electrolysis for hydrogen production Equipments and set up: Horizontal reactor 1.1. 2 RHVS2-2500R POWER CONVERTER AC TO DC The converter is supplied by Del high power (electronic corporation) with regulating voltage and current. When the electricity resistance is high in the electrolyte (liquid), voltage regulator is in control, or otherwise is to be controlled by -current regulator.

Technical data input: 220 VAC+/-10%, 50/60Hz, (single phase) O Output current 0~1200mA

DC voltage 0~2000V power : 2500W 1.1. 3 102G gas chromatogram 1.1. 4 MR chromatographic station, University of Ji Zhiang, Institution of Environmental Research and Engineering Center.) Technical data scope of input signal : 5mV~1VO accuracy: 1µV 1.1. 5 Other equipments 3 ways valves, water cooler, perplex glass tank, thermometer, heat couple, Al- 708 digital mV meter.

1.2 Testing liquid 1.2. 1 Distillated water produced by the laboratory.

1.3 Experimental procedure 1.3. 1 A flow diagram is shown in Fig. 28, wherein: 1: DC power source; 2: liquid bath; 3: reactor; 4: gas & liquid separator; 5: water chiller ; 6: gas volume measuring meter.

1.3. 2 Equipment function DC power source: provide high voltage DC.

Horizontal reactor: generation of non-thermal under liquid plasma.

Gas & liquid separator: to separate liquid from gas and return as chilled liquid.

Chiller : to condense any liquid vapor admixed in the gas and return to reactor.

Gas volume measuring meter: to measure the volume of gas flow.

1.4 Method and operation of the experiments (1) The experiment is conducted in according to the occurrence of plasma discharge. Six different levels of voltage are selected to produce under liquid

plasma with same reactor for the generation of hydrogen. They are: 1350V, 1450V, 1550V, 1650V, 1750V, and 1850V. Each experiment last 30 minutes and the experiment repeat three times under same set of conditions. The data obtained are than average out.

(2) Experimental procedures: a. Setting up equipments b. Check for air tightness c. Switch on the power and raise the voltage slowly near 1350V and then with fine tuning until plasma discharge occurs frequently and steadily. d. Maintain the above for five minutes allowing the state of plasma discharge settle to a steady mode. Allow the trapped gas in the piping to be expelled. e. Start collecting gas and measures its volume with time. Record all other data. f. Repeated the same experimental procedure for other level of voltage input with 1450V, 1550V, 1650V, 1750V, and 1850V.

1.5 Experimental Observations Plasma discharge at 1350V is observed to have few and limited lighting illumination on the electrode in comparing with those vigorous, steady discharging over a much larger electrode surface at voltage 1850V. The corresponding current input is also very much reduced. It has been recorded that the temperature at the cathode electrode rises with time until it reaches about 90C and gradually become steady. The color of plasma discharge appears to be orange and red Its color is greatly different from that of electric arc (plasma arc discharge) which appears to be sharp bright blue in color Data processing and analysis l\Aicrosoft Excel is used for processing the data and soft ware"Origin"is used for the graphic. In according to the curves, it appears that energy conversion for one unites of gas produced is in reverse to the productivity of gas. When the rate of gas production volume is high, the energy required will be less. It is observed when input

voltage at 1550V, it produces highest volume of gas and yet the energy consumption is relatively less. Over all speaking, with increases in voltage input, the energy conversion rate will be lowered. However the gas production is found to be of double curves, when input voltage is at 1450V, gas production is relatively less and energy consumption is also small. The experiment data and its curves have demonstrated the input voltage influence the productivity of hydrogen. In the plasma assisted electrolysis for hydrogen production a suitable input voltage has to be selected. With the condition under which the experiments are conducted, the best input voltage for gas production with relatively low energy consumption is at 1550V.

The temperature of the electrode and electrolyte liquid increased with the time of experiment. The temperature measured in the electrode is higher than that measured in the liquid.

Curves have been prepared based on the data obtained from the experiments.

Each duration of measurement is 10 minutes under which the curves are prepared.

The curves are prepared based on the first 10 minutes duration, see Fig 29.

The volume of gas produced in the first duration (10 minutes) and its energy consumption varies with voltage input, see Fig. 30.

In the first duration the energy consumption to produce one unit volume of gas changes with voltage input. b. The curves obtain in the second duration of 10 min (Fig. 31).

Energy consumption of second duration of gas production changes with voltage input (Fig. 32).

Fig. 32 shows the second duration energy consumption per unit gas volume vs voltage. c. Measurement of gas volume, power consumption and voltage input at 30 minutes (3rd duration).

Fig. 33 shows the gas production at the third duration, energy consumption vs voltage input.

Fig. 34 shows the third duration energy consumption per unit gas volume vs voltage. d. The curves derive from various experiments Fig. 35 shows the gas produced within 30 minutes, energy consumption vs. voltage input.

Fig. 36 shows the gas produced within 30 minutes, energy consumption per unit gas volume vs voltage input. e. Gas production vs time under various voltage input Fig. 37 shows the gas production vs time under voltage 1350V input.

Fig. 38 shows the gas production vs time with 1450V input.

Fig. 39 shows the gas production vs time with 1550V input.

Fig. 40 shows the gas production vs time with 1650V input.

Fig. 41 shows the gas production vs time with 1750V input. f. Total energy consumption, energy consumption per unit gas volume vs time at various voltage input.

Fig. 42 shows at 1350V input, the total energy consumption and energy consumption per unit gas volume vs time.

Fig. 43 shows at 1450V, the total energy consumption, energy consumption per unit gas volume vs time.

Fig. 44 shows at 1550V input, the total energy consumption and energy consumption per unit gas volume vs time.

Fig. 45 shows at 1650V input, the total energy consumption, energy consumption per unit gas volume vs time.

Fig. 46 shows at 1750V input, the total energy consumption, energy consumption per unit gas volume vs time.

Fig. 47 shows at 1850V input, the total energy consumption, energy consumption per unit gas volume vs time. g. Temperature at electrode and bath liquid vs time under various voltage input Fig. 48 shows at 1350V input, the electrode and bath liquid temperature vs time.

Fig. 49 shows at 1450V input, the electrode and bath liquid temperature vs time.

Fig. 50 shows at 1550V input, the electrode and bath liquid temperature vs time.

Fig. 51 shows at 1650V input, the electrode and bath liquid temperature vs time.

Fig. 52 shows at 1750V input, the electrode and bath liquid temperature vs time.

Fig. 53 shows at 1850V input, the electrode and bath liquid temperature vs time.

2. UNDER LIQUID PLASMA ASSISTED METHANOL TRANSFORMATION FOR HYDROGEN PRODUCTION 2.1 Equipments 2.1. 1 Horizontal reactor (self made)- 2.1. 2 RHVS2-2500R DC power source same as in 1.1. 2 2.1. 3 102G chromatogram as in 1. 1.3 2.1. 4 2.14 same as 1.14 2.1. 5 Other equipments same as 1.1. 5 2.2 Electrolytic liquid Distillated water produced by labortory methanol---description of purity.

Chemical formula : CH30H National standard GB683-93 Purity (CH30H) above.......... gg. 5% Density (20oC).......................................... 0.791#0.793g/ml Impurity 0. 001 % ; Water (H20).................................... 0. 1% ; Potassium hydroxide---purity description Chemical formula : KOH National standard GB2306-80 Purity KOH above 82% 2.3 Experimental procedure The reactor is placed inside a bath containing mixture of water and. methanol.

The open bath is constructed of perplex glass. A liquid and gas separator and a water cool chiller will be employed to separate and condense liquid vapor allowing the liquid return to the reactor and to maintain the concentration of methanol water mix. The gas outlet pipe will be connected to a water chilled gas volume-measuring meter.

(2) Equipment usage Power source provide steady supply of high voltage DC.

Horizontal reactor is where under liquid discharge is taking place in which the methanol water mixture is dissociated to produce hydrogen gas.

Gas and water separator separate the liquid coming out with the gas.

Water cool chiller will condensate liquid vapor.

Wet type gas volume measuring meter which measures the gas volume.

(3) Flow diagram, see Fig 54, wherein: 1: DC power source; 2: liquid bath; 3: reactor ; 4: liquid and gas separator; 5: water cool chiller ; 6: wet type-gas volume measuring meter.

2.4 Method and operation of experiments 2.4. 1 Method The experiments to reform methanol water mixture, to produce hydrogen, as electrolyte with the use of same reactor are conducted three times each lasting over 30 minutes for 7 different methanol water mixes i. e. 5%, 10%, 15%, 20%, 25%, 30% and 40% under the same experimental conditions. The data obtain from each set of (three times) experiment will be averaged.

2.4. 2 Operation procedure g. Setting up of equipments h. Checking air tightness i. Switch on the power, raising the voltage gradually, fine tuning when the target voltage of 1900V is near and steady plasma discharge illumination is observed. j. Maintain for five minutes which allows the reaction becoming steady. The gas trapped in the system is to be expelled. k. Collection gas volume and other experimental data begin.

2.5 Experiment Observation It has been observed that the temperature measured at the electrode and bath liquid in the first 0-10 minutes is not high. There is rarely any plasma arc being observed despite of the high voltage input. As the reaction continue on, the temperature recorded at the electrode and bath liquid has gradually risen. Plasma arc occurs more often than before which become more so at the later stage of 20-30 minutes duration. However in comparing with the continuous and steady normal plasma glow discharge (non-thermal), the plasma arc occurs only occasionally. With prolonged reaction there is occasion that the gas generated is faster than it can let out. The liquid in the reactor is displaced leaving a complete gas space then more extended plasma arc occurs.

2.7 Data analysis Microsoft Excel is used for the analysis of data. Soft ware"origin"is used for the graphic. In according to those curves showing that the production of gas increases with concentration of methanol water mixture and reduction in energy consumption.

At 25% concentration the gas production is at its highest in all three sets of tests.

However the gas production at 20% concentration is less than that recorded at 15%.

Its energy consumption is showing sign of fluctuation. It is observed that the lower the concentration the higher is the energy consumption needed to produce gas. The production of gas increase with increases in methanol concentration when the concentration is at relatively low level. The opposite happens more methanol concentration produces more gas at relatively high level of concentration. Based on the above observation, the gas production by reforming methanol with under liquid plasma is affected by its methanol concentration and the ideal concentration appears to be around 25%.

Following the increase of reaction time, the gas production increases with various methanol concentration. The energy consumption also increases but not linearly. The temperature of electrode and bath liquid also increase and that at the electrode temperature is higher than that in the bath liquid.

The following are the curves deriving from the experimental data. a. Gas volume vs time at various methanol concentrations at 1900V input.

Fig. 55 shows the production of gas vs time with methanol concentration at 5%.

Fig. 56 shows the production of gas vs time with methanol concentration at 10%.

Fig. 57 shows the production of gas vs time with methanol concentration at 15%.

Fig. 58 shows the production of gas vs time with methanol concentration at 20%.

Fig. 59 shows the production of gas vs time with methanol concentration at 25%.

Fig. 60 shows the production of gas vs time with methanol concentration at 30%.

Fig. 61 shows the production of gas vs time with methanol concentration at 40%. b. Energy consumption and energy consumption per unit gas volume vs time with various methanol concentration

Fig. 62 shows the energy consumption and energy consumption per unit volume gas vs time at 5% methanol concentration.

Fig. 63 shows the energy consumption and energy consumption per unit volume of gas vs time with methanol concentration of 10%.

Fig. 64 shows the energy consumption and energy consumption per unit gas volume vs time at 15% methanol concentration.

Fig. 65 shows the energy consumption and energy consumption per unit gas volume vs time at 20% methanol concentration.

Fig. 66 shows the energy consumption and energy consumption per unit gas volume vs time at 25% methanol concentration.

Fig. 67 shows the energy consumption and energy consumption per unit gas volume vs time at 30% methanol concentration.

Fig. 63 shows the energy consumption and energy consumption per unit gas volume vs time at 40% methanol concentration. c. Electrode (cathode) and bath liquid temperature vs time under various methanol concentrations Fig. 69 shows the temperature at electrode and bath liquid vs time with 5% concentration.

Fig. 70 shows the temperature change at electrode and bath liquid vs time with 10% methanol concentration.

Fig. 71 shows the temperature at electrode and liquid vs time at 15% concentration.

Fig. 72 shows the temperature at electrode and in liquid vs time with 20% methanol concentration.

Fig. 73 shows the temperature at electrode and in liquid vs time with 25% methanol concentration.

Fig. 74 shows the temperature at electrode and in liquid vs time with 30% methanol concentration.

Fig. 75 shows the temperature at electrode and in liquid vs time with 40% methanol concentration. d. Gas volume and energy consumption vs methanol concentration at different reaction period (duration).

Fig. 76 shows the gas volume vs methanol concentration at 9 to 10 min. duration.

Fig. 77 shows the energy consumption per unit gas volume vs methanol concentration in 0 to 10 min. duration.

Fig. 78 shows the gas volume vs methanol concentration from 10 to 20 min. duration.

Fig. 79 shows the energy consumption per unit gas volume vs methanol concentration from 10 to 20 min. duration.

Fig. 80 shows the gas volume vs methanol concentration from 20 to 30 min. duration.

Fig. 81 shows the unit gas volume energy consumption vs methanol concentration from 20 to 30 min. duration.

Fig. 82 shows the gas volume vs methanol concentration at 30 min.

Fig. 83 shows the unit gas volume-energy consumption vs concentration at 30 min. time.

Fig. 84 shows the hydrogen concentration vs methanol concentration. Note: B denotes oxygen gas, and no carbon dioxide and carbon monoxide is detected.

Fig. 85 shows a chromolithographic gas analysis of methanol plasma reformation.

About 15% of oxygen gas is also recorded in the hydrogen gas produced by the plasma-assisted electrolysis with distillated water only and methanol was not yet added. The chromatographic analysis of produced gas from methanol reformation shown that it is neither CO and C02. The complete absent of CO and C02 gas in the reformation of methanol water mixture is unexpected despite of repeated test with the

chromatogram that is geared to detect gas pollution such as CO, and C02. This is suspected that conductive reagent of KOH may have absorbed the CO or C02 gas in the process. The present of oxygen may also be the result that in the course of plasma dissociation 0, 02 and 03 is also produced which have not fully migrated to the anode horizontally placed below the cathode and some of the fine oxygen bubbles may also pass through the separating membrane and enter the inner reactor and collected in the same time with hydrogen. This may also explain that despite of the apparent boiling inside the reactor with bubbles, the net produced hydrogen gas is limited which may due to recombining with oxygen back to water.

Reformation of hydro-carbon liquid and gas fuel, and hydrogen rich compounds for hydrogen production Water is one of the primary source materials, which serves as carrier, conductor and confinement to the bubbles space where plasma corona and glow discharge would take place when adequate electro-potentials apply across single, or multiple electrodes pairs.

The hydrocarbon fuel methane (gas), methanol, diesel, gasoline, kerosene, ethane, natural gas, LPG gas, bio-diesel etc and hydrogen sulphur (H2S) are also good source material for hydrogen production.

The majority worldwide of hydrogen production conventionally is by high- pressure steam reformation of methane. This requires high pressure and high temperature. The production plant is large and costly to set up. Storage and delivery in association with the production are added cost for the supply of hydrogen gas.

The important of hydrogen as an alternative environmental clean fuel is well understood. The on coming of fuel cell technology demands economic and ready supply of pure hydrogen gas. To produce hydrogen with a small processor to enrich fuels for combustion engines and gas turbines will not only saving fuel consumption and also reduce polluting emission.

The proposed plasma reformation process can deal with gaseous fuel, liquid fuel. The gas fuel will be bubble into the reactor with inhibitor to slow down the upward flow of fuel gas. Since the dissociation of the hydrocarbon fuel will be mainly subjected to plasma dissociation which is similar to plasma assisted electrolysis process but with electrolytic liquid containing hydrogen rich compounds.

In the case of liquid fuel. it can either form mixture with water or to be emulsified with water. The percentage of fuel in the mixing depends on the type of fuel, its conductivity, boiling point, flammability and electrochemical reaction. The reformation is mainly due to partial oxidation either with the active OH-, O-, 02,03 created by the plasma dissociation. In the same time the hydrogen rich compound such as CH4 or CH30H will be dissociated directly with electrons collision. Since carbon dioxide is a major by products together with some other minor gases coming out from the impurity of the fuel, they will be separated by the convention absorption method or membrane separation method.

Transformation of hydrocarbon fuel by corona and glow plasma has been attempted by passing the hydrocarbon gas such as methane, natural gas, LPG and vaporized liquid fuel sometime mixed with water vapors through the plasma reactor.

They have all reported successful in producing hydrogen rich gas by corona discharge at atmospheric pressure by subjecting methane, vaporized methanol, diesel fuel with mixing of water vapor by passing through plasma gild arc reactor, wire in tube reactor and reactor proposed by MIT plasmatron and other gas phase corona streamer reactor.

The proposed under liquid plasma reactor has many advantage over the gas phase plasma reactor by being able to generate steady plasma glow discharge at a very much lower voltage from 350V to rarely 1800 V. with current in the range 100mA to 800mA in water.

The liquid media will also permit the application of ultrasonic waves with effect that will enhance the generation of glow plasma and thereby increase the overall transformation process. Again no external air or gas is needed to be introduced for the reaction. However, the hydrogen carbon gas such as methane, natural, LPG or hydrogen sulfurs gas can be introduced to work in conjunction and complementing

with liquid fuel in the reformation process. The fuel gases will enhance plasma discharge reformation to take place without relying on gas produced by electrolysis.

Those hydro-carbon fuel molecules that come in contact with the plasma discharge will be subjected to dissociation and partial oxidation depicted in the following : H20 +e # OH + H+ +e dissociation CH4 + e 9 CH3 + H+ +e direct plasma dissociation CH4 + H 9 CH3 + H2 reacting with H radicals CH4 + H20--> CO + 3H2 partial oxidation CO + H20 @ C02 + H2 water shifting CH30H + H2O # C02 + 3H2 electrolysis and partial oxidation H2S # S + 2H without experiencing oxidation H2S + 2H20 @ S02 + 3H2 partial oxidation S02 + 2H20 @ H2S04 +H2 Endothermic catalytic conversion of light hydro-carbon (methane to gasoline) CnHm + nH20 + nCO + (n + m/2) H2 With heavy hydro-carbon CH1,4 + 0,3H20 + 0, 4O2 # 0, 9CO +0, 1C02+H2 C8H18 + H20 + 9/202-6CO + 2C02 + 10H2 The hydrogen gas and carbon dioxide will be collected. The C02 will be separated by establish absorption or membrane separation method

The OH radical produced by the plasma dissociation will play an important role to oxidize the CH4 to produce CO which would further be oxidized to become C02. The same applied to methanol CH30H and H2S. The S is being oxidized to form S02 and further oxidizing to become S03 and subsequently react with H20 to produce H2SO4. This type of chemical reaction will be possible only with the encouragement of the highly chemical reactive and plasma catalytic environment. Not every CO will become C02 and sulphur particles may be observed in the precipitation.

Reactor There are number of reactors for the reformation of hydrogen rich compounds can be employed. Reactor such as wire in tube, tube in tube; single cell and multiple cell reactors; and the multi-electrodes without diaphragm separation. The tube in tube reactor and tower reactor with horizontal electrodes are suitable for treating both liquid and gas hydrocarbon and both in the same time. The anode and cathode is closely spaced with gap distant from 6 to 12 mm and are covered with dielectric gas retaining and current concentrating construction on. one side or. both sides of the electrode. One important aspect of the reactor is having the construction, which will accommodate the ultrasonic transducer, which would induce proper sonic cavitations uniformly, distribute through out the reacting volume. The size, shape and arrangement of the electrodes can vary but its size would be restricted by the electric power available. A small reactor electrode plate is quite adequate for good uniform discharge and high productivity. The size of reactor plate use in most of the experiments is in the range of 16 to 30cm2. It is preferable that. the non-discharging electrode having an electrode area larger than the discharging electrode with the dielectric gas retaining construction. With sufficient power available both anode and cathode electrode can be functioning as plasma discharging electrodes in the same -time. RThis is particularly favorable for the partial oxidation process.

In the case of emulsified oil water mixture it will best maintained with ultrasonic excitation which in the same time generating transient micro bubbles which will enhance the whole reactive process. Hydrocarbon gas may also introduce to the reactor to form air bubbles or trapped gas pocket for the ready formation of plasma glow discharge. Since the oily hydrocarbon fuel is highly dielectric this would require higher concentration of conducting reagent than that required for the plasma assisted water electrolysis, to maintain a suitable level of current density for the discharge to occur.

Reformation of methane gas by the under liquid non-thermal plasma is by bubbling the gas through the perforated horizontal electrodes of tower reactor or tube in tube reactor. Since the methane gas is to be oxidized by the plasma dissociated water molecule (OH-+ H+) to form carbon monoxide and hydrogen gas (CH4 + H20 @ CO +3H2. The CO will be further oxidized to form C02 with oxygen derived from the plasma dissociated water molecule and releasing two more hydrogen atoms (H2).

The resultant gas is either H2 or C02 with perhaps small amount of CO. The hydrogen gas will be collected with reasonable purity after the C02 or CO is removed by absorption or membrane separation. Since the methane gas may not thoroughly reformed with one past through the reactor, it is in the first place to regulate the gas flow rate to ensure suitable resident time for the reformation or to have the methane gas recovered for the next round of reformation or to have the gas going through a series of reactor to made sure methane gas is fully utilized. The later case may not be energy efficient.

Reformation of methanol for hydrogen production can be in the first place achieved by ordinary electrolysis by partial oxidation. When CH30H subjected to plasma discharge irradiation will become reactive with the oxidizing species and radicals dissociated from water molecules. The conventional electrolysis will also contribute to the over all production of hydrogen gas. Reformation of methanol water mixture will achieve better efficiency when plasma discharges in working in conjunction with ultrasonic excitation and cavitations. Several types of reactor can be adopted for the methanol reformation such as tower reactor with horizontal electrodes, tube in tube reactor, transverse flow reactor and etc. These types of

reactor offer very active oxidizing species and hydroxyl radicals for the needed in the reformation.

Reformation of heavy oil such as diesel by under liquid plasma discharge will be with emulsified liquid. The best way to maintain a thorough emulsification of diesel fuel and water is by ultrasonic excitation. Micro droplets of diesel will be encapsulated by water. It is again observed that the conductivity of the emulsified liquid is very low as diesel oil is dielectric and current can only be conducted through the water film in between. This has rendered the need of more electrolytes added, especially when the diesel contend increases. Bubbles are not easy to be produced by electrolysis due to low current flow. It is therefore advantage to either introduce gas to the reactor from outside or to produce ultrasonic cavitations amidst the liquid volume in the same time of emulsification of water oil mixture. Tower reactor, tube in tube reactor and transverse flow reactor are all suitable for heavy hydrocarbon fuel reformation provided that adequate ultrasonic transducer is properly located to ensure effective excitation and cavitations distributed through out the liquid volume. Pulsed power supply will enhance the plasma generation and electrode heating will assist the generation of bubbles at the discharging electrode.

Under liquid plasma reformation of LPG gas- Equipment 1. Horizontal reactor 2. RHVS2-2500R high voltage power converter supplied by Del Electronic Corporation. Voltage and current can be regulated. With high resistant loading voltage is in control, other wise the input power will be regulated by current control.

Technical data Input : 220 VAC+/-10%, 50/60Hz, single phase.

Output: current 0-1200mA DC voltage 0~2000V Power rating: 2500W

3. Ultrasonic Bath Shanghai Scientific Ultrasonic Equipments Co.

Model : SK3300LH Frequency: 40,59KHz Max power rating: 160W Adjustable power input: 70%, 100% External dimension: 32cm*17cm*28cm Bath dimension: 30cm*15cm*15cm Capacity: 6L 4. Other equipments pressure reducing valve ; gas reservoir; gate valve ; two gas volume measuring meters; gas and liquid separator ; water cool chiller ; thermometer 5. Materials LPG gas: obtain from gas station KOH as conducting reagent.

Distillated water produced by laboratory water distillatory.

6. Experimental flow diagram, Fig. 86, wherein: 1: LPG gas tank; 2: pressure reducing valve ; 3: gas reservoir; 4: gas gate valve ; 5: gas volume meter: 6: gas and liquid separator; 7: horizontal reactor; 8: liquid bath; 9: ultrasonic transducer; 10: water chiller ; 11: gas volume meter; 12: power source; 13: thermometer.

Experimental method and procedure (1) Method The experiment is conducted under electrolytic distillated water of 3.5 L with 0.25% KOH as conductive additive. The LPG will be introduced to the reactor when a

steady plasma discharge is generated. The main compositions of LPG gas are C3H8 and C4H10. There will be an increase in gas volume if the LPG gas is experiencing plasma dissociation. The output gas volume should be greater than the input gas volume measured by the gas volume meter, which will serve as indication whether the LPG gas can be dissociated by the non-thermal plasma under liquid.

(2) Procedure Switch on the reactor and raise the voltage and current input until a steady plasma is generated. A certain amount of LPG gas will passed on to a gas reservoir with reduced pressure. Switch of the gas supply and turn have the gas gate valve so that the LPG gas will be introduced to the reactor in controllable manner through the perforated electrode at the underside of the reactor. Allow the reaction for five minutes to allow those entrenched gas in the pipeline to be expelled before taking various measurement reading with time.

Experimental Observation Non-thermal plasma was generated with the electrolytic liquid. The LPG gas enters the reactor through the perforated anode electrode at the bottom of reactor and is subjected to plasma irradiation near the discharging electrode. The color of the plasma discharge is yellowish red. There is large quantity of bubbles boiling inside the reactor which some how inhibited the entry of the introduced gas. There is a certain amount of LPG gas being trapped underside of the bottom electrode. In order not to spill the gas, which will influence the outcome of the experiment, the introduced gas is carefully regulated.

Experimental data Table 3 1: experimental result without application of ultrasonic Time/min voltages current/mA No. 1. gas No. 2 gas Power meter meter reading reading/L reading/L kW. h 0 1985 87 94.15 15.475 24. 667 30 1985 93 94. 905 16. 36 24. 800 Table 4 2: 1St. experimental result with application of ultrasonic irradiation time/min voltage/V current/mA No. 1 gas I No. 2 gas Power meter meter reading reading/L reading/L kW. h 0 1985 130 0. 42 3. 75 25. 093 10 1985 120 0. 934 4. 48 25. 170

Table 5 3: 2nd experimental result with application of ultrasonic irradiation time/min voltages current/mA No. 1 gas No. 2 gas Power meter meter reading reading/L reading kW. h 0 1985 135 0.52 4.12 25. 45 10 1985 | 122 0. 983 5. 29 25. 529

Analysis of experimental data Table 6 Experiment without application of ultrasonic irradiation time/min No 1 gas No. 2 gas Gas vol. Power Power Gas meter meter Increased/L consumption consumed production volume volume/kW. h per unit L/h. record/L record/L gas volume /KWh/L 0-30 0. 755 0. 885 0. 13 0. 133 1. 023 0. 26 Table 7 Experiment with application of ultrasonic irradiation Experime time/mi No. 1 No. 2 Gas Power Power Gas nt n gas gas volume consume consume productio meter meter increased/d d per n L/h. volume volume L/kW. h unit gas record/record/volume L L KWh/L First 0-10 0. 514 0. 73 0. 216 0. 077 0. 3565 1. 296 second 0-10 0. 463 0.707 0. 244 0. 079 0. 323 1. 464

The experiment shows that ultrasonic irradiation is greatly influencing the gas volume out put. In the rudimentary gas analysis H2, C02 and C3H8 are detected. The increase gas volume in 10 min test is about 50%. In order to improve the gas out put higher current input would be advantages. It is regrettable that this is prevented by the limiting capacity of the power converter.

Reduction of metal and mineral oxide process It is costly and polluting in the process of mineral refinement. To remove oxygen from the oxide is either by reacting with higher electro-positive elements, which is economically forbidden, or by exposing the metal oxide to C, CO, and hydrogen inside a high temperature furnace such as the case in iron production. The electrolysis of molten melt of Al203 or Ti02 to extract pure metals Al or Ti respectively consume large quantity of electricity, use of expensive refractory and electrode materials and polluant emission which render these two useful metals very expensive and inhibit their common application.

An under liquid plasma reductive process to reduce oxide of ore or metals are proposed. The plasma discharge irradiation to the metals oxide in a highly catalytic environment will interact with the active hydrogen atoms derived from the plasma dissociation of water or methane or methanol water mixture and introduced hydrogen gas together with the assistant of ultrasonic excitation would be sufficient in many instances to dislodge the most stubborn oxide.

There is report that research is underway to extract Al from Al203 by electrolysis. Aluminium is electrode wined to cathode from porous Alumina anode electrode. Reduction of Ti02 and Al203 by hydrogen plasma discharge is also in active research elsewhere with the aim to refine these two useful metals economically.

Tube in tube reactor wire in tube reactor can be used for the reduction process. This two reactor can easily modified for continue processing the granular fine of the mineral or metal oxide. The metal oxide will be exposed to the influence of highly active hydrogen atoms and subsequently the oxygen in the metal will be removed. This would not be a problem for those electro-positive elements but would present some difficulty for oxide such as Al and Ti.

The oxygen is strongly bonded with the parent metals such as Api203 and Ti02 which can not be easily reduced. This rudimentary horizontal reactor serves as demonstration that metal oxide can be refined by exposing its granular fine to plasma

discharge irradiation, ultrasonic excitation and in a highly reactive environment with the active hydrogen atoms. Additional hydrogen can be derived from the plasma dissociation of methane gas introduced to the reaction chamber where CO and atomic H are produced. Similarly by plasma dissociation of the methane water mixture that active'hydrogen an C02 are also produced to supplement those reductive atomic hydrogen. Hydrogen gas can also bubble into the reactor and any excess will be collected and recharging back to the reactor.

Reduction of Al203, Ti02, TiF3, TiO, ALCL3 will be taking place in the following manner.

Where Ti02 +6H (2H2) # Ti +2H20 Al203 +6H (3H2) # Al +3H2O TiF3 + 3H (3/2H2) # Ti + 3HF The alternative is to have Ti02 +H2S04- TiOS04 + H20 TiOS04 + 2H i Ti + H2S04 or TiO + 2H # Ti + H20 and Ti02 +4HCI o TiCI4 + 2H20 TiCl4 + 4H o Ti + 4HCI where Tical4 is ionic and is soluble in water The above reaction is under influence of non-thermal plasma that the oxide of ores or metal is subjected to a highly catalytic environment and come in contact with the reactive atomic hydrogen whereby the oxygen will be taken out. To enhance the matter further the whole reaction process is also subjected to the sonic excitation.

The colloidal suspension of the fine granular oxide will collide with each other that at the point of impact temperature would rise over 1500 to 3000°C and local melting is reported. The high temperature and pressure of collapsing sonic bubble will work in conjunction with the plasma glow discharge irradiating the oxide particles with atomic hydrogen with localized high temperature due to collision and cavitations implosion

which in the end remove the oxygen. The refine metals will be in powdery form down to nano size.

The other method of extracting and refining metals from its oxide is to subject the ionic solution of the metal such as AIC13 to a electrolysis process which is reported to have achieved efficiency of 3KW h/kg of Al. The whole process can be further improved with the plasma electroplating technique with the proposed under liquid glow plasma discharge. The Al will be deposited on the cathode electrode. Part of chlorine gas will comes out from the anode side and many will react with the active hydrogen to form HCI.

The fine granular metal oxide is placed inside a horizontal reactor on top of cathode electrode. A close matrix separator membrane to prevent the metal oxide to cross over separates the anode electrode above and below the cathode. The whole reactor is submerged inside an ultrasonic bath. Ultrasonic waves will penetrate the membrane separator to cause the granular metal oxide in colloidal suspension. The oxide will. subjected to the under liquid plasma glow discharge irradiation and atomic hydrogen reduction. The percentage of metal oxide being reduced after a period of time is evaluated. Metal oxide of Ti02 will be put to test. Methane water mixture will be employed as the liquid media which will produce larger amount of active atomic hydrogen serving as reduction agents.

Experimental results Under liquid plasma reduction of Ti02 with ultrasonic irradiation Equipments 1. Horizontal reactor self-made

2 : RHVS2-2500R high voltage DC power.

Supplied by Del Electronics Corp. with regulating voltage and current control.

Technical data : Input : 220 VAC +/- 10%, 50/60Hz, single phase.

Output: current: 0#1200mA DC voltage 0-2000V Power: 2500W 3. Ultrasonic bath . supplied by Shanghai Scientific Ultrasonic Equipment Co. model : SK3300LH frequency: 40,59KHz max power output: 160W adjustable power out put : 70%, 100% external dimension: 32cm*17cm*28cm bath dimension: 30cm*15cm*15cm capacity: 6L 4. Other instruments: thermometer, heat couple thermometer, desiccators, centrifugal machine..

5. Materials > Ti02 : above 98% pure Methanol above 99.5% pure KOH above 82% pure 6. Experimental method and procedure The liquid in the ultrasonic bath is consisting of 25% methanol, 0.05% KOH conductive additive and distillated water with a total volume of 3L. Fill the gas

trapping chamber of the reactor with Ti02 powder and sealed with nylon cloth on both side to stop out flow of powder during reaction. Switch on the ultrasonic bath and then the reactor. Adjust the voltage and current input until a steady plasma is generated. Continue the reaction for 60 minutes. Collect all the bath liquid and solid particles from the bath. The solid matter from the bath liquid is separated by centrifugal machine and put to dry inside a vacuum chamber. The solid matters is then put to X-ray diffraction examination to identify any changes to the Ti02.

Record of experimental data Table 8 Time/min, Voltage/v Power/Kw. h Current/mA Pond Temp/°C 0 1850 0 315 46 10 1850 0.09 235 53 20 1850 0.254 422 57 30 1850 0.387 500 60 40 1850 0.49 238 68 50 1850 0.571 301 76 60 1850 0.665 224 75 Figures 87,88 and 89 show the graphs showing the energy consumption, current and temperature of bath liquid vs time at 1850V input.

Experimental observation Steady plasma is maintained through out the test. Because of large volume of gas produced within the gas trapping chamber together with the ultrasonic irradiation that the fine Ti02 powder was forced out of the gas trapping chamber where the intended oxide of titanium is supposed to be reduced with present of active hydrogen atoms and carbon monoxide dissociated from methanol with the catalytic influence of plasma glow discharge. It appears that most of the fine powder is forced out and

escape to the surrounding bath liquid, which turn to milky color at the very early stage of the test. As the experiment proceeds the milky bath liquid turned to yellowish milky color and became thicken with increased viscosity. This has caused some problem in separating the solid matter from the bath liquid, which has taken a long time with highest revolution speed of the centrifugal machine. The solid matter was dried inside a vacuum chamber. There was no change in color during drying process.

Result from X-ray diffraction examination The X-ray diffraction test was conducted by the testing center of South China University of Technology. Figures 90A and B and 91A and B are the graph and charts from the test: Figures 90A and B before experiment and Figures 91A and B after experiment.

From the chart and-data of The X-ray diffraction test it demonstrated that the powder is Ti02 with its"d"value grouping 3.512, 1.892, 2.376 and its strength of distribution are: 100,29, 22. Fig. 92 shows the standard diffraction test data of Ti02.

Comparison of the X-ray diffraction test data before and after the experiment showed the following"d"value was not present in the Ti02 powder before the experiment. They are: a 2. 089, 1. 480, 2.400 b 2. 400, 2. 329, 2.213 These figure matched those in the region of TiO (titanium monoxide) and TiN (n-Ti3N2-x). Fig. 93 shows the standard chart of x-ray diffraction"d"value of TiO and Fig. 94 shows the standard chart x-ray diffraction"d"value of TiN.

Conclusion There is no record that Ti is detected. But with the rudimental test it indicate that some changes has taken place that Ti02 is reduced to TiO and some of them converted to TiN most likely due to the present of nitrogen of the dissolved air in the bath liquid.

It is suspected that the poor experimental result is due to the early escape of the Ti02 from the reaction gas-trapping chamber where the oxide powder has not

been properly subjected to reduction action; the powder collected for x-ray diffraction test is from the bath liquid and not from the remnant powder inside the gas trapping chamber; Hydrochloric acid of higher concentration should be used as conductive- additive and catalytic reagent to transformed the Ti02 to TiC) 4 to facilitate the reduction process; The discharging electrode (cathode) should also put to examination to find out whether Ti may have been deposited on its surface; the horizontal reactor design is not suited for the reduction test (vertical wire in tube or tube in tube reactor proposed in the patent specification is more suitable) as the oxide powder has not been subjected to plasma reduction action for a reasonable period and the reduction process is proceeding in molecular and atomic base; and finally the voltage and current input is limited that the glow discharge may lacking the strength necessitate for the reduction reaction.

Despite of all the inadequacy of the experiment, it has still demonstrated that the under iiquid piasma discharge with the provision of atomic hydrogen and plasma catalytic reaction environment is a worth wise method for reducing oxide of metals (metal oxide has been reduced including Ti02 in gaseous reaction chamber with hydrogen gas as reducing agent under non-thermal plasmas glow discharge). This has. already been proven that metal object under water can be deoxidized or reverted by simple electrolysis process in under water archaeology or in hydrogen gas plasma chamber.

Decontamination of liquid The problem of pollution is a major issue affecting every living being in this planet earth. A lot of effort has been spending by Governments, universities and private enterprises seeking comprehensive process to deal with vast variety of pollution. Polluting gas emission from industries and motor vehicles produce large quantity of C02 causing global warming; NOx, VOC, and particulates causes cancer and smog; S02 causes acid rain. Decontamination of gases discharge from industries at time is costly to neutralize and remove which urgently need a comprehensive and economic treatment process to reduce the overall production cost. Water contamination is another major issue. It contaminate fresh water source unfitted for human consumption and sea near shore killing marine live. Government

in the world is passing stringent law setting pollution standard, which demands development efficient and economic ways or process in controlling and decontaminating pollutions. The present proposed invention is put forward as a versatile process, which can treat a variety of contaminant in separate or together.

Corona discharge and glow plasma discharge as non-equilibrium plasma has been developed for applications in the decontamination a wide range of noxious chemical compounds and recalcitrant chlorinated organic compounds such as dichloro-ethane, pentachlorophenol, perchloroethylene, chlorom, carbon tectrachloride, organochlorine presiticides, endocrine disrupter, dioxin and etc. It is also capable to sterilize tough microbial, bacteria and biological contaminants present in ground water such as cryptosporidia parvum. Noxious gas emission such as NOx and SOx can also be neutralized by passing them through the wet reactor, which includes the removal of particulates with the polluted emission. This is mainly due to the ability of plasma in creating a very reactive catalytic environment for those compound, which would normally very stable and inactive, to be reduced, oxidized or neutralized by reacting with the OH* radicals, atomic hydrogen H+ and other oxidative species such as 0-, 02,03, H202 etc. present and is reported of having high efficiency especially in dealing with diluted contaminant.

Microbial and bacteria is removed by both oxidations when come in contact with the oxidative species such as 03,02-, O-, H202, OH*. In the same time they are subjected to the electro-mechanical stretching of the cell wall, which weakens its oxidative resistance. Especially, with the application of ultrasonic cavitations implosion and shock waves created by pulse power are incorporated in the reactive process. Again report of over 99% sterilization is not uncommon.

At the present most of the treatment work is conducting in gases environment, by spraying or vaporizing the contaminated liquid over the plasma discharging electrodes, or to produce plasma discharge irradiating over liquid surface which contains the undesirable contaminants, or by passing the polluted gas through dry reactor which sometime mixed with water vapor or using plasma torch irradiating the pollute object.

Surface water contact plasma glow discharge system has also been developed as an decontamination process in the name of Plasmate. Under water plasma by pulsed high voltage electric discharge with high current input to dissociate the water to produce H and OH* radicals to treat bacterial and microbial decontamination has also been reported with success.

The proposed under liquid plasma is a low energy consumption system, which produce steady plasma by utilizing the present of bubbles. The voltage require in dealing with wide range of liquid of having uncontrollable electrolytic properties is ranging'from 350V to 3000V and current density ranging from 1 to 2 Amp/cm2. It is not only producing the highly reactive environment with supply of oxidative radicals and reductive atomic hydrogen spreading over large volume of liquid making it highly effective as a decontaminate process which is also economic and easy to operate.

The under iiquid plasma is having the advantage-to--decontaminate several polluants in the same time and is aiso having a very active gas and liquid interaction rendering it highly effective as treatment process. Liquid waste containing harmful chemical, bacteria, microbial, heavy metals, noxious gas emission, polluted air and odor can be treated in the same reactor simultaneously.

Recalcitrant organic chlorinated organics materials in water, which include dichloromethane, pentachlorophenol, chloroform and carbon tetrachloride, will either be oxidized or reduced degraded to C02 and chlorine. While the pathogens in drinking water such as cryptosporidia with thick phospholipids wall protecting the trophs is in the first place being stretched and weaken and subsequently break down by the oxidizing species. Some of the oxidative species such as OH radicals, O-, 02-, and 03 are present in quantity and are more active than chlorine and other mild oxidants. It has the advantage that no chemical is needed as oxidation agent, which sometime result a secondary pollution.

Heavy metals in dilute solution can be extracted or removed through a simple electrolysis process by turning the metal to hydroxide which could than be remove by filter. In the case of soluble metal ions it can also be extracted by deposition on to cathode electrode, which can further be facilitated by the plasma electroplating process owned by the inventor using the same under liquid bubble plasma process.

The treatment of NO, S02 and particulates is to pass the polluted gas through the reactor where the particulate will be removed and the NO is either oxidized to become N02 and N03 by 0-, or 03. It can also be reduced to N by the active hydrogen. N03 will react with water to become nitric acid. N02 is considered not a noxious gas. S02 with 03 or oxygen radical to form S03 can easily oxidize S02, which than react with water to become H2SO4. When the said gas is introduced to the reactor it can be utilized as a gas bubble for plasma discharge especially when this gas bubble is collected or retain near the electrodes.

The effectiveness of non-thermal plasma discharge in treating carcinogen organic compounds and polluted gases are well established. Removal or reduce the amount heavy metals, arsenic and mercury to an acceptable safe level in low concentration from water have been successfully carried out by simple electrolysis process. The extraction efficiency is further improved with the present of under liquid plasma discharge where some of them will be readily react with the OH radicals to become metal hydroxide or to be deposited by the very active plasma electroplating (deposition) which has been adequately proven.

Further experiments in this area are unnecessary. Adequate information can be drawn upon from many research work already been carried out. Concentrated effort has been spend to search for a better way to generating steady plasma glow discharge under liquid by utilizing the bubbles which will enable the. manufacturing of simple and economic reactor requiring low power input that work well in treating a wide scope of contaminants.

Sterilization of drinking water in municipal scale can be simplified by adopting the under liquid plasma discharge which will effectively neutralize and degrade carcinogen organic compounds in the water by in the first place create the dissociate and active catalytic environment which encourage the breakdown of the inert chemicals and in the same time subject it to the active reductive and oxidative radicals. The heavy metals dissolved in the water will also be removed or reduced in the same time through the plasma electrolysis and electroplating as described previously. The biological contaminants will be sterilized by the highly oxidative environment existed during the glow discharge. The effectiveness of combine

treatment of portable water fit for human consumption is further enhanced by the adoption of ultrasonic cavitations and shock wave with pulsed power supply.

The entire sterilization process does not require any added chemicals such as ozone, chlorine and any electrolytic additive. The impurity in the pretreated liquid will be adequate to serve as conductor for the under water plasma discharge to take place. Any excessive ozone, which has not been used up in the oxidation process during the plasma discharge, will be easily neutralized by present of active hydrogen atoms. Hydroxyl radicals (OH) are one of the most aggressive oxidizing agents, which are produced in quantity that will do most of the useful work. There will be no chlorine remnant left in the water, as it is unnecessary.

The under liquid plasma technique will be useful in food industries for low temperature sterilization and removal of odour. The same may also find its use in paper industry in fragmentation and de-iignifications the fluidised pulps, treating the highly polluted discharge, and treating fabrics and dyes in textiles industries.

There are several types of reactors can be employed in the decontamination process. The separation membrane diaphragm in the wire in tube and tube in tube reactor is no longer required. Other reactor such as transverse flow reactor and tower reactor can all be adopted.

The reactor can be arrange in such way that the plasma discharge occurs either on the cathode or anode and in both electrode as long as good gas trapping cover is provided on the electrode. Since many of the decontamination action is relying on the present of strong oxidation agents such as hydroxyl radicals, atomic oxygen, ozone, singlet oxygen and hydroperoxyl radicals, plasma discharge on the side of anode electrode enhanced with the gas retaining cover will cause the formation of said species represented by the following equations: H20 + e OH + H + e dissociation H20 + e- H20+ + 2e ionization H20+ + H20 9 H30+ + OH dissociation

02 + e 9 02* + e excitation 02 + e e 20 +e dissociation 02 + e 0-+ 0 dissociation 02 + O @ 03 association OH + OH- H202 association In some chemical contaminants can only be broken down by reduction with active atomic hydrogen, which would require of plasma discharge in the cathode electrode. In the tower reactor (Fig. 7) and transverse flow reactor (Fig. 6) it is possible of having the gas retaining cover on one side of electrode facing the side of the opposite electrode with the gas retaining covers, so that alternating zone of oxidation and reduction are created in the reactors to deal with a variety of contaminants.

Production of hydrogen by plasma dissociation of water molecules is the result of electron collision, which is different from the conventional electrolysis, which separates the dipole water molecules by the electro-induction. They also have different sets of requirements to dissociate water molecules for the production of hydrogen.

Conventional electrolysis Plasma glow discharge under water, according to the present invention 1. Low voltage and high current density High voltage and relatively low current density ion 2. High concentration of electrolyte (up to Low concentration electrolyte 25% KOH) (0. 01% KOH) low electrolytic requirement.

3. Avoid bubble attachment to the electrodes Bubbles smothering the electrodes is welcome to create dielectric barrier.

4. Electrode space distance is not restricted. Electrode space distance has to keep close as far as possible.

5. Water molecules is split by induction Water molecules is dissociated by electron collision.

6. Large production unit is required for Small production unit efficiency and productivity. favor decentralization of production.

The reactors and gas trapping and retaining structures enclosing the electrode is made of perplex plastic. No sign of burning is observed in the plastic covering plate directly over the discharging electrode is observed and the light emission observed is orange/red color (burning of hydrogen) which is distinctively different from the plasma arc which is bright blue color when the voltage is brought beyond the glow discharge voltage level. Burn mark will be observed after plasma arc discharge. This proves that the o plasma glow discharge with orange yellow color is non-thermal.

Sterilization of mulberry iuice with under liquid plasma Equipments : same as for methanol reformation but without the need gas separator, water chiller and gas vol. meter.

Materials for testing Mulberry juice supplied by Ghangtung University of Agriculture, mulberry research laboratory.

Distillated water supplied by own laboratory.

Experimental flow diagram: Fig. 95 The equipment consist mainly a power source, the electrolytic bath, horizontal reactor, thermometers, temperature measuring heat couple, Experimental method and procedure Mix 2L of distillated water with 15% concentrated mulberry juice in the perplex glass bath. Switch on the reactor and maintain the voltage at 1200V and keep on stirring the liquid. Obtain 5mL sample of juice at 20 min and 40 min time from the bath.

Counting the number of bacteria existed-before-and after-each session of test follows the specification laid down by People Republic of China standard GB4789.2- 84. Counting the number of mold colony existed before the test and after each session test follows the specification laid down by People Republic of China standard GB4789. 15-84.

Experimental data and analysis Table 9 Voltage, current and temperature record Cathode Time/min Voltage/v PondTemp/°c Temp/c Current/mA Power/Kw. h 0 1200 22.5 27.5 243 0 20 1200 48 61 320 0.241 40 1200. 53 63 169 0.211 Table 10 Micro-organism Test Result Time Bacterial Lump Sum Mold Colony Sum Min Number. ml~1 Number. ml~ 0 3400 37000 20 1300 17000 40 90 10

5.5 Observation The natural conductivity of the mulberry juice is high. The current during the reaction fluctuated around 200mA and voltage settled at 1200V. The plasma glow discharge is steady and evenly spread. The temperature measured at cathode electrode is fluctuating about 62°C. The bath liquid is maintaining around 50°C After treatment, the color and smell of the mulberry juice has no obvious change.

Conclusion Fig. 96 and Fig. 97 are graphs showing the number of bacterial and moid colony count respectively vs time during the sterilization treatment.

The under liquid plasma can be utilized for sterilization the bacteria and mold colony in the mulberry juice. It is especially effective to sterilize mold and achieve four-digit sterilization at 50°C. It is also considered effective in destroying bacteria.

The above experiment has demonstrated that the under liquid plasma can be utilized as a new method for sterilization bacteria, microbial for liquid food and to be adopted for sterilization portable water and waste treatment work which impose no restriction on voltage and current input, and high temperature.

Under liquid plasma reformation of emulsified diesel with ultrasonic irradiation Equipments 1. Horizontal reactor self-made 2. RHVS2-2500R DC high power converter with regulating voltage and current supplied by Del Electronics Corp input: 220 VAC+/- 10%, 50/60Hz, single phase. output current 0-1200mA DC voltage 0-2000V Power rating: 2500W 3. Ultrasonic Bath Shanghai Scientific Ultrasonic Equipment Co.

Model : SK3300LH Frequency: 40,59KHz Max. power output : 160W Adjustable power output: 70%, 100% External dimension: 32cm*17cm*28cm Bath dimension : 30cm*15cm*15cm capacity: 6L 4. other equipments : three way valve, water chiller, thermometer, heat couple.

5. Materials -Diesel oil from gas station Emulsify additive : Chemical composition: C34He20, PH: 5~7 Distillated water produced by the laboratory

Experimental method and procedure Experimental flow diagram: Fig. 98, wherein: 1: DC power source; 2: ultrasonic bath; 3: reactor; 4: gas/liquid separator; 5: water chiller ; 6: gas vol. meter.

(2) Experimental method.

Add 1.25% emulsify additive and 0.02% KOH as conductive reagent in the bath liquid which contain 25% or 50% diesel fuel with distillated water. The ultrasonic bath is switch on for 5 min to allow the diesel oil properly emulsified with water.

Switch on the reactor and adjust the voltage and current input until steady plasma is achieved in about 5min. During the experiment the bath liquid is to be stirred continuously. Measure and collect the gas volume and other data.

Experiments are conducted with 25% and 50% diesel emulsion.

Experimental observation The color of diesel is clear liquid with slight tune of yellow, but turn to milky light brown color after emulsified with ultrasonic irradiation. The light brown color is properly due to the emulsion additive.

The diesel emulsion begin to separate and form diesel oil layer near the cathode discharging electrode at the upper side of the reactor on passage of electricity. As the result the current dropped rapidly. T he diesel oil stratification becomes obvious. At this instance much higher voltage is required to cause electric break down of the dielectric oil layer.

The gas produced is smoky and its smell resembles tail pipe emission. The gas is not easily burn. Experimental data Table 1 1 50% Diesel Gas Time Voltage Current Cathode Temp Power Volume Consumption/ /min /V /mA /°C /Kw.h /ml kW. h/L 0 1850 130 71. 6 0 0 10 1850 112 77. 6 0. 067 540 0. 1241 20 1850 163 88. 1 0.129 1360 0. 09485 30 1850 187 89. 2 0. 211 1740 0. 1213

Table 12 25% Diesel Gas Time Voltage Current Cathode Temp Power Volume Consumption/ /min/V/mA/°C/Kw. h/ml kW. h/ml 0 1850 149 72. 8 0 0 0 10 1850 237 82. 5 0. 085 30 2. 833 20 1850 166 89 0. 149 80 1. 862 30 1850 189 94.7 0.212 160 1.325

Analysis of experimental data Fig. 99 is the graph showing temperature of cathode electrode vs time. a. Figures 100 and 101 show the current vs time for 50% &25% diesel concentration respectively.

b. Figures 102 and 103 show the power consumption vs time for 50% &25% diesel concentration respectively. c. Figures 104 and 105 show the gas production vs time for 50% &25% diesel concentration.

Conclusion It is possible to dissociate or reform diesel oil.

It will of course be realised that the above has been given only by way of illustrative example of the invention and that all such modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth.