Technical Field

The present invention relates to a method and a device for generating hydrogen based on water.

Background Art

Known methods for generating hydrogen based on water use the principle of electrolysis, wherein a direct current (DC) voltage is applied between two electrodes placed in an electrolytic solution containing water. The applied DC voltage induces a decomposition of neutral molecules into ions and electrons whose movement in the solution establishes electrical current. Respective chemical decomposition half-reactions occur at each electrode, generating reaction products including hydrogen.

Technical Problem

These methods however present several limitations. Firstly, the electrolysis requires DC voltage, which is commonly extracted from alternative current (AC) power from large-scale power generation systems as well as local end user power distribution systems. Therefore, to operate an electrolytic cell, cumbersome and loss-inducing AC/DC conversion appliances may be needed. Alternatively to AC conversion appliances, DC power sources such as batteries or fuel cells might be used. However, such power sources generally require cost-intensive infrastructure and large quantities of fuel. Although hybrid options have emerged that combine solar and wind sources to produce electricity for the electrolytic cell, such sources require large implementations.

Secondly, in electrolytic cells, the chemical half-reactions occur localized at the electrodes, thereby subjecting the electrodes to degradation and thus reducing life-span of the electrodes. For instance, the electrodes may require expensive materials or coatings to withstand a wear due to oxidation/reduction. Thirdly, in order to obtain good working efficiency, many conventional electrolytic cells can require additional components such as bypass(es), separator(s), diaphragm(s), or the synthesis of artificial electrolytic solution(s) using additive(s). These components could further increase the cost of operation of such electrolytic cells.

Solution to Problem

In view of the above, it is an object of the present invention to provide a method and a device for generating hydrogen economically and with improved efficiency. This object is achieved, in one aspect, with the method according to claim 1. Such a method comprises the steps of placing at least two electrodes in water; connecting the at least two electrodes to an AC power source, which is configured to supply AC power, and supplying the AC power to the connected electrodes.

In the context of this invention, it can be understood that water refers to water in liquid state or a dilute aqueous solution. An electrode refers to an electrically conducting object configured to establish an interface of electrical interplay with a non-metallic medium. An AC power source is a source of electrical power with at least two terminals, configured to supply said terminals with an alternating voltage, for example with a sinusoidal voltage.

The inventors have found that, contrary to the conventional understanding, using AC power for electrolysis can be efficient, and the use of an AC power source can generate hydrogen in significant quantities. The inventors have designed a method wherein when the electrodes are placed in water and supplied with AC power, the effect of water decomposition, also known as splitting or dissociation, can be magnified. In particular, the inventors have found that the electric and magnetic components of the electromagnetic field of the AC power interact with the water molecule in a way that enhances the tendency of the water molecule to decompose. Thus, with this inventive method, oxygen and hydrogen can be generated by decomposition of the water molecule at lower cost and improved efficiency. In addition to the efficient production of green hydrogen, no pollutants may be derived in the process, no additives or no electrolytes may be used and, consequently, in case of need, simple and pollutant-free water can be returned to the environment.

Further, depending on the level of hydrogen generation, at least a portion of the generated hydrogen can be fed back into the system with self-generated electrical energy, thereby further improving its sustainability and efficiency. Compared to conventional electrolysis, with this method, loss due to the conversion of alternating current to direct current can be avoided, and using of batteries with polluting waste elements can be avoided. Taking advantage of a continuous production process, the method can be industrially scaled.

By using an AC power source, the invention can allow for dispense of cumbersome appliances typically required in conventional electrolytic cells, such as AC/DC converters, platinum electrodes, polluting batteries or fuel for fuel cells, or electrolyte additives. Further, the invention relies on readily available water, for example, sea or tap water, and thus can easily be implemented. In a preferred embodiment of the invention, the AC power source is a three-phase AC power source. A three-phase AC power source is a source of electrical power with at least three terminals, configured to supply respectively connected electrodes, for example, with a sinusoidal voltage. The three voltages may have substantially identical effective value and may be around 120 degrees out of phase relatively to each other. By using a three-phase power source, a multiplicity of electrodes and a multiplicity of connection arrangements can be realized to thereby further improve the dissociation of water molecules and to thereby improve the efficiency of hydrogen generation.

In a preferred embodiment, the three-phase AC power source may be configured to operate in a single-phase arrangement. In the single-phase arrangement, the at least two electrodes are connected to two of the at least three terminals of the three-phase AC power source such that the three-phase AC power source provides single-phase AC power to the electrodes. With the singlephase arrangement, a simpler electrode connection can be realized, and at the same time, hydrogen can be generated with lower energy consumption.

In a preferred embodiment, the three-phase AC power source may be configured to operate in a two-phase arrangement. In the two-phase arrangement, the at least two electrodes are connected to two of the at least three terminals of the three-phase AC power source such that the three- phase AC power source provides two-phase AC power to the electrodes. With the two-phase arrangement, hydrogen generation can be achieved with an advantageous balance of improved hydrogen generation efficiency and lower energy consumption.

In a preferred embodiment, the three-phase AC power source may be configured to operate in a three-phase arrangement. In the three-phase arrangement, the electrodes are connected to at least three terminals of the three-phase AC power source such that the three-phase AC power source provides three-phase AC power to the electrodes. With the three-phase arrangement, a higher quantity of hydrogen but at a relatively shorter time, when compared to a single-phase or two-phase arrangement, can be achieved.

In a preferred embodiment of the invention, the power may be supplied at a predetermined AC voltage. The supply of a predetermined AC voltage, for example with a constant effective voltage, by the three-phase power source can enable stable dissociation of water.

In a preferred embodiment of the invention, the predetermined AC voltage can be between 1 V and 500 V, preferably between 12 V and 380 V, and more preferably between 18 V and 96 V. The inventors have found that a particularly efficient dissociation effect can occur in these voltage ranges.

In a preferred embodiment of the invention, said power may be supplied with a predetermined AC frequency. The predetermined AC frequency may allow for better control of the electromagnetic field generated by supply of power to the electrode assembly.

In a preferred embodiment of the invention, the predetermined AC frequency may be between 15 Hz and 500 Hz, preferably 50 Hz and 240 Hz, and more preferably between 60 Hz and 120 Hz. According to findings of the inventors, with these frequency ranges, an efficient water dissociation can be realized.

In a preferred embodiment of the invention, said water may be contained in a sealed container. Using a sealed container can allow for prevention of unwanted substances contaminating at least the electrodes and water, thereby providing a cleaner environment for the dissociation of water.

In a preferred embodiment of the invention, said water may be distilled water. The use of distilled water could allow for a reduction of unnecessary and interfering substances or elements in the water, which could otherwise be ionized and thus produce unwanted electric currents. Further, said interfering substances may also contain molecules that can dissociate together with the water molecule and thus may produce contaminating gases, which may reduce the purity of the generated hydrogen and oxygen mixture.

In a preferred embodiment of the invention, said water may have a predetermined conductivity. By using water with a predetermined conductivity, the water dissociation can be controlled.

In a preferred embodiment of the invention, said method may further comprise a step of recirculating the water in a water recirculation system. A step of recirculating water can allow for removing gas, such as hydrogen and/or oxygen bubbles attached to the electrodes or from walls of the sealed container and can enable the gas to be released to the atmosphere. Further, by recirculating the water, temperature and distribution of gas can be balanced. In addition, recirculation can enable the gas produced by the dissociation to be removed to keep the dissociation process at optimal level.

In a preferred embodiment of the invention, the method can further comprise a step of cooling the recirculated water. By cooling the recirculated water in which the electrodes are placed, energy losses due to the heat and vapor generation may be kept minimal. In a preferred embodiment of the invention, the water recirculation system can be operated intermittently. The intermittent operation of the water recirculation system can reduce power requirements of a recirculation operation.

In a preferred embodiment of the invention, the method may further comprise a step of collecting generated gases in the sealed container. A step of collecting the gases may allow for further processing of the collected gases.

In a preferred embodiment of the invention, the electrodes may be metallic plates, in particular stainless steel plates. Stainless steel plates may present the advantage of being particularly resistant to corrosion and thus enable a longer life span of the electrodes.

The above-mentioned object of the invention is also achieved by a device according to claim 18 configured to generate hydrogen based on water. The device in particular is suitable for carrying out the method according to any one of claims 1 to 17. The device comprises at least two electrodes configured to be placed in the water, and an alternative current (AC) power source, wherein the at least two electrodes are configured to be connected to the power source, and the power source is configured to supply AC power to the connected electrodes. This device allows for the implementation of the method of the invention and thus provides the advantageous effects of the method, namely an effective water dissociation with improved efficiency that is free of the drawbacks of electrolytic cells, such as high DC power requirements.

Brief Description of Drawings

These, as well as other objects and advantages of this invention will be more completely understood and appreciated by careful study of the following more detailed description of the presently preferred exemplary embodiments of the invention taken in conjunction with accompanying drawings, in which:

Figure 1 depicts a flowchart of a method for generating hydrogen based on water according to the invention.

Figure 2A shows a schematic view of a device for generating hydrogen based on water according to an embodiment of the invention.

Figure 2B shows a schematic view of a device for generating hydrogen based on water according to a variant of the embodiment of the invention. Figure 2C shows a schematic view of a device for generating hydrogen based on water according to another variant of the embodiment of the invention.

Figure 3 shows a schematic view of a device for generating hydrogen based on water according to another variant of the embodiment of the invention.

Description of Embodiments

A general principle for generating hydrogen based on water according to the invention is described with reference to Figure 1. Figure 1 illustrates a flowchart of a method for generating hydrogen based on water according to the invention. The method includes a step S1 of placing at least two electrodes in water, preferably contained in a sealed container.

The electrodes are placed in water, in particular distilled water with a predetermined conductivity. The predetermined conductivity can be measured or set before step S1 of the method. The predetermined conductivity of the water before step S1 is preferably in the range of 0.5 pS/cm and 10 pS/cm, more preferably in the range of 0.5 pS/cm and 2 pS/cm, when, for example, measured at a temperature between 1 °C and 30 °C. The use of water that has not been conventionally distilled but purified using other methods is equally suitable. In further variants, instead of distilled water, tap water or sea water could also be used. In another variant, the conductivity can depend or be varied based, for example, on mineral content in the water. In a preferred embodiment, the predetermined conductivity of the water is within the range of 0.5 pS/cm and 10 pS/cm at reaction temperature (for example, between 1 °C and 30 °C) and the conductivity value is maintained within that range regardless of whether the conductivity is measured before the start, during the reaction and after the reaction, including any previous usage of the water and/or minerals/salts content in the water. In the present variant, a volume of 80 L of water is used. However, the quantity of water is not limited thereto, and depending on the size of the device, the quantity of water can be varied.

The water in which the electrodes are placed at step S1 has an initial temperature between 1 °C and 30°C, preferably between 5°C and 10°C. The invention is not limited to this temperature range. In further variants, water at an ambient temperature, for example between 20°C and 30°C, or above, could also be used.

The electrodes are placed in the water such that the surfaces of the electrodes which are configured to establish interface with water, are substantially immersed in the water. By substantially immersed, it is meant that a fraction of the electrode surface could preferably remain outside the water and accessible for manual manipulation, in particular for the establishment of an electrical connection with a power source. For example, at least 50% of volume of the electrodes can be immersed in the water. In a preferred embodiment, at least 70% of volume or all parts of the electrodes is fully immersed in the water.

In a step S2, the electrodes are connected, in particular, electrically connected, to an AC power source. The AC power source is configured to supply AC power to the electrodes via its terminals. In this step, at least one first electrode is connected to one terminal of the AC power source, and at least one second electrode is connected to another terminal of the AC power source. For example, one electrode can be connected to one terminal of the AC power source, and a second electrode can be connected to the other terminal of the AC power source. The AC power source can be a single-phase, a two-phase or a three-phase AC power source. In one preferred variant, each of the electrodes can each be connected to a respective terminal of the AC power source, preferably in a single, two-phase or three-phase arrangements. The connection of the electrodes to the AC power source will be further described with reference to Figures 2A to 3.

The electrical connection between the electrodes and the terminals of the AC power source can be achieved using any conventional means including such as suitable wires, cables, insulators, circuitry and the likes. The order of steps S1 and S2 can be exchanged or varied. For example, in other variants, the electrodes can first be connected to the terminals of the AC power source and the electrodes connected to the terminals can then be placed in the water.

In a step S3, the AC power is supplied to the connected electrodes. The AC power source is configured to provide the electrodes with a predetermined voltage of alternating current (VAC) power. The predetermined AC power is between 1 VAC and 500 VAC, preferably between 12 VAC and 380 VAC, and more preferably between 18 VAC and 96 VAC.

The predetermined AC power is supplied with a predetermined AC frequency. According to this embodiment, the predetermined AC frequency is between 15 Hz and 500 Hz, preferably 50 Hz and 240 Hz, and more preferably between 60 Hz and 120 Hz.

In a preferred embodiment, the AC power source is set at 20 V per phase for a three-phase voltage of around 35 VAC, and with a frequency of around 89 Hz. In one example, these parameters of the AC power source can provide the most effective hydrogen generation for a water conductivity of 1.10 ' ⁴ S/m.

In a preferred embodiment, the AC power is continuously supplied for the duration over which hydrogen generation is desired, or until the power source has depleted. During the duration of power supply, the electrodes placed in water generate an electromagnetic field that decomposes water. In particular, the alternating current generates an electromagnetic sine wave in which the electric and magnetic components make up the wave in a perpendicular arrangement. The electric and magnetic components of the electromagnetic field of the AC power interact with the water molecule in a way that enhances the tendency of the water molecule to decompose. In particular, the action of this composite sine wave can, according to the predetermined frequency, achieve the separation of hydrogen and oxygen from the water molecule, thereby causing dissociation. More particularly, the magnetic component can accelerate the excitation of hydrogen and oxygen ions, resulting in the dissociation of these elements with very little electrical power. The configuration thus does not depend on a defined or fixed cathode and anode. This dissociation is an electrochemical REDOX reduction-oxidation reaction due to the exchange of electrons. Thus, with this inventive method, oxygen and hydrogen can be generated by decomposition of the water molecule at lower cost and improved efficiency.

According to an analysis carried out with a potentiostat by means of cyclic voltammetry, it was determined that the dissociation process occurs immediately on supply of the AC power from the AC power source. Taking advantage of the solubility of oxygen in water, the above result can be confirmed, for example, using an oximeter. In an example, the oximeter (not shown) detected an increase of the oxygen level in the water varying from 3.2 mg/l at the beginning of the reaction to 8.9 mg/l in a period of 60 min.

In a step S4, the water is recirculated in a recirculation system. In this step, a fraction of the water in which the electrodes are placed is exchanged with an identical quantity of water, which has not yet been subjected to steps S1 to S3. For example, the recirculation can be operated by means of a hose system and a pump. This step allows for flow effects generated by the water recirculation to desorb gas bubbles from electrode surfaces, or from container walls.

In particular, this step of recirculating water can allow for removing gas, such as hydrogen and/or oxygen bubbles attached to the electrodes or from walls of the sealed container and can enable the gas to be released to the atmosphere. Further, by recirculating the water, temperature and distribution of gas can be balanced. In addition, recirculation can enable the gas produced by the dissociation to be removed to keep the dissociation process at optimal level. The recirulation system (illustrated in Figure 3) can comprise pumps, device(s) using the principle of Bernoulli effect and/or gravity, compressors, and the likes. Preferably, the recirculation is operated intermittently rather than continuously, so as to reduce the power requirements of the recirculation operation without compromising the above-mentioned dissociation process and advantageous effects of the invention.

In a step S5, the recirculated water is cooled. In this step, the temperature of the water recirculated from the sealed container is reduced before reinsertion in the sealed container in a subsequent exchange of the recirculation operation. The recirculated water is cooled using a cooling means, for example by providing a separate recirculation container with water frozen to ice, and connecting said container to a hose system of the recirculation system. By cooling the recirculated water, energy losses due to the heat and vapor generation may be kept minimal. In further embodiments, other cooling means can be used, for example a refrigerating machine.

In a step S6, the generated gas is collected in the sealed container. The gas, for example in the form of bubbles of hydrogen, oxygen or water vapor, which is generated in step S3 of the method is removed from the sealed container. The generated gas can comprise hydrogen and oxygen which can be separated and collected by any known conventional mechanism and/or devices for various downstream uses. Thus, the collected gas can then be further processed.

An embodiment of a device 100A configured to generate hydrogen based on water according to the invention is described with reference to Figure 2A._The device 100A is configured to carry out the general principle of the generation of hydrogen based on the water according to the invention as described above with respect to Figure 1 , and the features thereof also apply to this variant and therefore are not repeated in the following.

The device 100A comprises an assembly 1A of two electrodes 3, and an AC power source 5 connected to the assembly 1A. In this embodiment, a first electrode 3 is connected to one terminal 6a of the AC power source 5, and a second electrode 3 is connected to another terminal 6b the AC power source 5.

In this embodiment, each electrode 3 takes the form of square, monolithic plates of a thickness of 2mm each, wherein each side of a plate has a length of 20cm. However, the present invention is not limited thereto and there are no constraints on the shape, dimensions and/or geometry of the electrode plates. In particular, the dimensions of the electrodes can be chosen based on the amount of the desired hydrogen, and the related power source and installation capacities. For example, it could be preferable to use an electrode with a plate length two order of magnitudes greater than plate thickness. In other embodiments, instead of square plates, many other electrode geometries could be used, for example rectangular, annular, spherical or tubular electrodes, or plates of concentric cylinders or plates bent into for example sinusoidal shapes.

In this embodiment, the electrodes 3 are arranged upright, side-by-side, for example in the fashion of a rack or a book shelf. In other words, the electrode plates are arranged in parallel to each other in the x-y plane and perpendicular to the y-z plane of Figure 2A. Each electrode thus provides a cross-section that is, in the x-z plane, vertical with respect to a horizontal direction z, which could represent a direction of rack progression and of flow. The assembly 1 A thus consists of a number of electrodes arranged in the form of a capacitor with water as dielectric insulator. The number of electrodes is not limited to two, however, at least two electrodes are connected to the terminals of the AC power source.

In this embodiment, the electrodes 3 of the assembly 1 are metallic plates, in particular stainless steel plates, for example plates of 316L austenitic steel. This material is devised to be particularly corrosion-resistant and durable. In other embodiments, alternative conductive materials could suitably be selected for the electrodes, such as silver, copper or aluminum.

The first and second electrodes 3 that are connected to the terminals 6a and 6b of the AC power source 5 are connected by means of an electrical connection. The electrical connection between the electrodes 3 and terminals 6a, 6b can be achieved using any conventional means such as suitable wires, cables, insulators, circuitry, and the likes. For example, a 2.5 mm2 diameter insulated copper cable according to EN 13602:2013 standard can be used as conductor for the electrical connection.

In the embodiment shown in Figure 2A, no constraints are placed on the nature of the AC power source 5 and the origin of the electrical energy provided, as they do not affect the suitability of the device described for generating hydrogen. For example, the AC power source 5 can be a common household plug providing a single-phase voltage of 230 VAC at a frequency of 50 Hz, or 120 VAC at a frequency of 60 Hz. The AC power source 5 can, for example, also be a commercial power instrumentation whose output can be parametrized and which draws power from a grid consumption point or from a household power output, or directly from an energy source such as a battery or solar power installation. In particular, the commercial power instrumentation can be a three-phase AC power source in the form of a Wye-configuration power generator. As an example, the AC6900 by Keysight, the 2003RP by TTi, or the GF3031 by GFLIVE can be used. With such commercial power instrumentation, voltage and frequency of the power output can be set to efficiently generate hydrogen based on water. Other alternative power sources to the above named devices could also be used without departing from the invention. For example, a Delta- configuration three-phase AC power generator, or a Wye-configuration power generator with a Neutral terminal can be also be used.

With the inventive device, an alternating current is applied to the connected electrodes at a specific frequency and voltage. This configuration can generate an electromagnetic sine wave in which the electric and magnetic components make up the wave in a perpendicular arrangement and interact with the water molecule in a way that enhances the tendency of the water molecule to decompose. In particular, the magnetic component can accelerate the excitation of hydrogen and oxygen ions. This can result in the dissociation of these elements with very little electrical power, thus generating hydrogen based on water at lower cost and improved efficiency.

A variant of the embodiment of a device 100B configured to generate hydrogen based on water according to the invention is described with reference to Figure 2 B._The device 100B is configured to carry out the general principle of the generation of hydrogen based on the water according to the invention as described above with respect to Figure 1 , and the features thereof also apply to this variant and therefore are not repeated in the following.

The device 100B comprises an assembly 1 B having a plurality of electrodes 3. Each electrode 3 is arranged, for example, in the fashion of a rack equally spaced, for example, from each preceding and succeeding electrodes, except for the end electrodes 3. In this embodiment, a distance separating two electrodes 3, for example, from the electrode surfaces, is around 6 mm. However, there are no constraints in the arrangement of the electrodes 3 in relation to each other and in further embodiments, different arrangements of the electrodes 3 towards each other could be used.

As illustrated in Figure 2B, the device 100B further comprises a three-phase AC power source. Figure 2B illustrates three example configurations of the three-phase AC power source referenced respectively as 5A, 5B, and 5C. In a preferred embodiment, the device can connect the electrodes 3 of the assembly 1 B to any one of the three-phase AC power sources 5A, 5B and 5C. Each of the sources 5A, 5B, and 5C provide at least three power outputs, or phase terminals V1 , V2, V3. The power source 5A is a three-phase AC power source in Wye-configuration without a Neutral terminal but with a grounded terminal. The power source 5B is in Delta-configuration. The power source 5C is in Wye-configuration with a fourth terminal N, which is a Neutral terminal.

In this embodiment, a first electrode 3 is connected to one phase terminal, for example, V1 or V2 or V3, of one of the three-phase AC power sources 5A, 5B or 5C, and a second electrode 3 is connected to another phase terminal (other of V1 , or V2, or V3) of the same AC power source 5A, 5B or 5C. The remaining electrodes 3 are not electrically connected to the AC power source. In the embodiment shown in Figure 2B, the first and second electrodes 3 are end electrodes of the electrode assembly 1 B, and they are connected to the AC power source, and the electrodes 3 provided between the two end electrodes 3 are not connected directly to the AC power source.

Thus, the device operates in a two-phase arrangement. The electrodes 3 not connected to the AC power source operate by electromagnetic field induction and thus contribute to the water dissociation generating hydrogen. Preferably, the electrodes not connected to the AC power source are placed between the two connected electrodes 3. In alternative embodiments, either one or both of the end electrodes 3 can be not connected to the AC power source, while one or two electrodes between the two end electrodes are connected to the AC power source. Thus, the electrode assembly can be energized with different induction combinations to vary the capacitance level and the effectiveness of the hydrogen generation.

The operation of the device in a two-phase arrangement can provide an advantageous balance of hydrogen generation efficiency and low energy consumption.

In an alternative embodiment relating to the three-phase AC power source 5C, instead of connecting the second electrode 3 to a second phase terminal (i.e., other of V1 , or V2, or V3) of the power source 5C, the second electrode 3 can be connected to the Neutral terminal N of the power source 5C. Thereby, a single-phase arrangement can be established, resulting in the similar operation and effects of the previous embodiment illustrated by Figure 2A, namely the generation of hydrogen by dissociating water with a reduced consumption of electrical energy.

Another variant of the embodiment of a device 100C configured to generate hydrogen based on water according to the invention is described with reference to Figure 2C._The device 100C is configured to carry out the general principle of the generation of hydrogen based on the water according to the invention as described above with respect to Figure 1 , and the features thereof also apply to this variant and therefore are not repeated in the following.

The device 100C comprises a three-phase AC power source 5A as previously described, and an assembly 1C of electrodes 3 comprising twenty individual electrodes 3. In this embodiment, each electrode 3 of the assembly 1C is connected to one of the three phase terminals 7, 9, 11 of the power source 5A.

The V1 -phase terminal 7 of the power source 5 is connected to one subset of the electrodes of the assembly 1C. The V2-phase terminal 9 is connected to a second subset of the electrodes 3 of the assembly 1C and the V3-phase terminal 11 is connected to a third subset of electrodes 3 of the assembly 1C. The first subset and a second subset of the assembly 1C of electrodes each comprise seven individual electrodes 3. The third subset of the assembly 1 C comprises six individual electrodes 3. The invention, however, is not limited to these number of electrodes.

Each electrode is arranged equally spaced, for example, from each preceding and succeeding electrodes, except for the end electrodes. In this embodiment, a distance separating between two consecutive electrodes 3, for example, from the electrode surfaces, is around 6 mm. However, there are no constraints in the arrangement of the electrodes in relation to each other and in further embodiments, different arrangements of the electrodes towards each other could be used. In Figure 2C, for visibility purposes, the separation between the last and second-to last electrode has been increased in order to display electrode perforations 15 (described below).

In the embodiment, each of the individual electrodes 3 exhibits seven circular perforations 15 through the electrode surface. The perforations consist of holes in the electrodes that present circular circumference in the x-y plane and cross the electrodes in z-direction. Three of the seven perforations 15 are disposed centrally in the electrode and remain unfilled in order to provide openings for fluid flow. The four remaining perforations 15 are located in the vicinity of the respective corners of each electrode 3 and provide fixation means for the assembly 1 (illustrated in figure 2 by a support structure 13 for the electrodes 3). The support structure 13 is made of insulating material, for example acryl. It can be appreciated that the number of perforations 15, for flow and/or for fixation, as well as the type of support structure used, is determined in accordance with operation and installation requirements of the device for hydrogen generation, and can vary greatly from one implementation of the invention to another. Therefore, in different embodiments, in particular in arrangements that are not rack-like, no support structure, or a very different support structure could be implemented. The perforations and support structure can also be provided in the embodiments of Figures 2A and 2B.

In this embodiment, the total number of electrodes 3 of the assembly 1C of the device 100C corresponds to the sum of the number of electrodes 3 in each of the first, second and third subset connected to a respective terminal 7 (V1), 9 (V2), 11 (V3) of the three-phase AC power source 5A. However, the number of electrodes is not limited to this example. In further embodiments, the number of individual electrodes 3 of the assembly 1C could be identical, or differ. The electrodes 3 of the assembly 1C are arranged such that the assigned electrode three-phase power source terminal repeats on every third count. In other words, the electrodes 3 of the assembly 1C are arranged in a repeating alternating sequence V1 - V2 - V3 of the respectively assigned power source terminal.

This preferred embodiment magnifies the effect of dissociation of water. The magnetic components of the electromagnetic field of the AC power interact with the water molecule in a way that enhances the tendency of the water molecule to decompose, with a greater total hydrogen yield in a shorter time when compared to the single-phase or two-phase arrangement.

Another variant of the embodiment of a device 100D configured to generate hydrogen based on water according to the invention is described with reference to Figure 3, which is a preferred embodiment. The device 100D is configured to carry out the general principle of the generation of hydrogen based on the water according to the invention as described above with respect to Figure 1 , and the features thereof also apply to this variant and therefore are not repeated in the following. In addition to all the features described with respect to the embodiment of Figure 2C described above, which will not be repeated, this device 100D further comprises a sealed primary reaction container 21 filled with water 19, in which the electrode assembly 1C is placed.

The device 100D further comprises a recirculation system 23 comprising a recirculation container 25 hydraulically linked to the primary reaction container 21 by means of a hose system 17. The hose system 17 can comprise inlets and outlets in the container 21 and 25, and hose elements for establishing the hydraulic link between said inlets and outlets in container 21 and 25. For example, a 13mm diameter hose set with 2 bar pressure (30psi), and corresponding 13 mm inlets and outlets can be used as the hose system. The hose system is equipped with a pump 27 for flowing water in and out of the primary reaction container 21 , as well as with valves to open and close the hydraulic links. For example, the pump 27 can be an electrical pump powered by the three-phase AC power source 5A, or by another electrical power source.

The device 100D comprising the containers 21 and 25, hose system 17 and pump 27 can be fully hermetically sealed so as to avoid any gas or water leakage. The recirculation container 23 is provided with a cooling means (not represented). The primary reaction container 21 is equipped with a gas collection outlet 29 for collecting the gas released by the water 19.

The containers 21 and 25 in which the water 19 is contained are preferably made of material that is a gastight, watertight, chemically inert and electrically inert, for example high-density polyethylene such as found in a conventional intermediate bulk container. Thus, water leakage and gas leakage of generated hydrogen or oxygen can be avoided, and introduction of interfering liquids or polluting gases in the closed container system can also be avoided. Further, use of such a material can avoid interfering electrical effects on the electromagnetic field generated, as well as the risk of chemical pollution from the container.

The device 100D described above represents an embodiment of the invention for generating hydrogen based on water, which is improved by providing recirculation means and cooling means to the device The recirculation of water allows for gas bubbles attached to the electrodes of the electrode assembly 1C or from walls of the container 21 to be removed and to be collected. Further, by recirculating the water, temperature and distribution of gas can be balanced and the dissociation process be improved.

Reference signs:

100A, 100B, 100C, 100D: Device for generating hydrogen based on water

1A, 1 B, 1C: assembly of electrodes

3: Stainless steel plate electrode

5, 5A, 5B, 5C: AC power source

6A, 6B: Terminal of the AC power source

7: V1 -phase terminal connected to a 1st electrode subset of the three-phase AC power source 5A 9: V2-phase terminal connected to a 2nd electrode subset of the three-phase AC power source 5A

11 : V3-phase terminal connected to a 3rd electrode subset of the three-phase AC power source 5A

13: Support structure

15: Electrode perforation

17: Hose system

19: Water

21 : Primary reaction container

23: Recirculation system

25: Recirculation container

27: Pump

29: Gas collection outlet