Field of the invention

The invention relates to a process for the production of a compound and to a micro reactor for performing such process.

Background of the invention

The petrochemical, chemical and biochemical processing industries are facing extensive challenges imposed by the rapidly changing market situation and the changes in the world economy, increasing social pressure and tightening legislation on protection of our ecosphere and the huge pressure from shareholders on capital productivity of money invested in this industry.

The market situation in Europe and in North-America in particular is very though for the processing industries due to high costs (feedstock, energy, labour) and due to worldwide installed capacities exceeding market demand. A specific additional problem for the European processing industries in this respect is that the European plants on the average already are relatively old and small scale in comparison to newly started plants and plants under construction in the Middle-East and Far-East. This makes the current competitive position of the European plants relatively weak. To a lesser extend this also applies for the North- American plants. The current situation for Europe and North-America may be expected to also extend to developing areas within the next decade.

Global competition has turned the market into a fully customer driven market the past decade. This implies that suppliers to this market are facing fierce competition where only those will survive that meet the following conditions:

- Deliver at low(est) cost

- Deliver products that meet the requested specifications at a high quality level meeting imposed quality standards (Cpk- values, 6-Sigma, ...)

- Deliver the requested volume(s) of products at the requested time

- Cover a product portfolio that aligns with the fluctuations and changes in market demand Market price of delivered products and services is a key decisive factor today for most customers. If a customer can choose from two or more vendors that deliver about the same quality and that can deliver the requested product volume at the requested time, he will select the supplier that reliably delivers at minimum cost. To be competitive in this market the price of products and services is a key success factor. Too high a price directly implies that the orders will go to competition. Quality is an equally important key success factor. A supplier that delivers products that don't meet requested specifications would not be selected. Most customers don't want to build up stocks. Pressure on capital productivity at customer side makes that suppliers are forced to deliver at demand of the customer. As a consequence suppliers have to be flexible in delivering varying product mixes and product volumes at relatively short notice. To meet this requirement a supplier has the possibility to build up large stock themselves, which of course is a very expensive way of working, or to move towards producing at demand thus minimizing internal stocks and consequently minimizing the capital invested in materials and (semi-)manufactured products.

Market demand is very volatile today. Worldwide competition and the availability of a large production capacity worldwide make that customers can do their shopping globally in many cases. The available means of communication make that information is globally available without severe restrictions. Enabling very short product development cycles strengthens market position of manufacturers. The short product development cycles create the opportunity for a manufacturer to discriminate from competition and to create competitive advantage. Very short product development cycles, so strong innovativeness, help manufacturers to follow volatility of the market. Like the current situation in semiconductors, consumer electronics, automotive and telecommunications also the process industries will be facing the pressure from shortening product life cycles and the increasing sensitivity for time- to-market of new products. The manufacturers that have control over their full product development cycles and over their time-to-market will have a very significant competitive advantage. A break-through technology that enables very tightly controlled and fully predictable operation of processes and that furthermore enables instantaneous manipulation of processes at demand will change the competitive game completely.

Today's flexibility in the operation of processes in petrochemical, chemical and biochemical processing industries is limited by the lack of effective control handles for the processes. Current control of the processes in the petrochemical, chemical and biochemical processing industries is done by manipulation of one or more of the four main process conditions that determine the ongoing processing in reactors and bio organisms:

- Concentration of relevant reactants or nutrients

- Pressure

- Temperature - Residence time

Manipulation of any of these conditions requires direct manipulation of a major mass or energy flow. These manipulations can only be realized with severe resolution, rate- and amplitude limitations. As a consequence, control of the processes can only be done within a very restricted bandwidth, which does not or only hardly exceeds the natural bandwidth of the process (i.e. relatively long response times instead of instantaneous response) and within a very restricted dynamic range (i.e. range between largest possible response and minimum observable response is relatively small: <100).

US6190507 describes a method for non-thermal plasma after treatment of exhaust gases the method comprising the steps of providing short rise time (about 40 ps), high frequency (about 5G hz), high power bursts of low-duty factor microwaves sufficient to generate a dielectric barrier discharge and passing a gas to treated through the discharge so as to cause dissociative reduction of the exhaust gases. US6190507 also includes a reactor for generating the non-thermal plasma.

US2002085968 describes a method for producing self-assembled objects comprising single-wall carbon nanotubes (SWNTs) and compositions thereof. In one embodiment, the US2002085968 involves a three-dimensional structure of derivatized single-wall nanotube molecules that spontaneously form. It includes several component molecule having multiple derivatives brought together to assemble into the three-dimensional structure. In another embodiment, objects may be obtained by bonding functionally-specific agents (FSAs) groups of nanotubes into geometric structures. The bond selectivity of FSAs allow selected nanotubes of a particular size or kind to assemble together and inhibit the assembling of unselected nanotubes that may also be present.

US2007059235 describes a rapid start reactor that can be used, for example, in a water gas shift reactor of a fuel processor. The reactor has a catalyst support structure with one or more surfaces overlaid with an active coating that includes a catalyst. The active coating heats upon exposure to a non-thermal energy source. The reactor also includes a generator of nonthermal energy for applying non-thermal energy to the active coating. Methods for operating such a reactor during transient and/or start-up conditions are also provided in US2007059235.

US 2004206618 describes a catalyst system that can be used, for example, in a water- gas shift reactor of a fuel processor. The catalyst system includes a foam-type catalyst support structure and a non-thermal plasma generation device for generating a non-thermal plasma in the catalyst bed in order to enhance the catalytic reaction taking place in the catalyst bed. The use of the foam catalyst support structure allows the plasma to permeate throughout the catalyst bed structure.

WO 2009103017 describes a method for converting a methane gas to liquid fuel forms a non-thermal plasma with radicals and directs the plasma over a catalyst to convert the radicals to higher hydrocarbons in liquid form. The method can be performed in a reactor such as a microwave plasma reactor, or a pulsed corona discharge plasma reactor. A system for performing the method includes a methane gas source, a reactant gas source, a reactor and a catalyst. Summary of the invention

These restrictions (as indicated above) in process operation severely limit both flexibility and achievable quality in the operation of processes. The resulting relatively long process start-up, shutdown and transition times make that processes have to be operated at relatively large volumes per batch of a product type to keep total costs per batch of good product acceptably low. It hampers responsiveness of the industry to fluctuations in demand both with respect to volume as well as with respect to product types/ product specifications. The process industries require technology that preferably enables a direct response in manufacturing to specific demand coming from the market. Technology is needed that supports production transitions and recovery from process upsets in very short time intervals. The technology needed is similar to the technology applied today in electronics, mechatronics, automotive and aerospace applications. The control techniques applied in these environments enable operation over very large dynamic ranges (e.g. audio and video equipment operating at signal to noise ratios up to 140 dB, which is equivalent to a ratio between largest possible response and minimum observable response of 10.000.000), very large frequency ranges (e.g. servomechanisms having a bandwidth of up to 1000 times the natural bandwidth, electronic circuits having bandwidths of up to 100.000 times the natural bandwidth of the applied components) and at accuracy levels, which are extremely high compared to the basic specifications of the underlying process design (e.g. DVD players use weak, very light mechanical constructions that nevertheless are operated at positioning accuracies of <500nm with very fast response times.

The main basic component that enabled the above mentioned high performance applications in electronics, mechatronics, automotive and aerospace is the transistor. The main characteristic of this transistor is that it can precisely manipulate a primary energy flow (electrical current) almost instantaneously with a very low energy demanding manipulation (basis current or gate voltage manipulation) and with a very high resolution. This easy, accurate and very fast to realize manipulation enables the design of systems that can be virtually operated towards extreme conditions where the system would normally be damaged completely, if such condition would be realized and persist even only a very short time. The very fast, easy to realize and robust manipulability of the system makes that the system can nevertheless be operated at conditions that intend to move the system very rapidly towards these extreme conditions, but where the movement is stopped or even reversed long before safety limits are exceeded. This today allows the design of e.g. cars where control systems completely determine the dynamic behaviour, ease of driving, comfort and robustness at one hand and at the same time the use of remaining freedom in engine operation to minimize emissions and fuel consumption. This same technology allows the design of airplanes (fighters) that can make turns invoking accelerations that reach or easily can exceed the maximum g-forces a human pilot can handle without losing conscience.

The same technology also enabled the design of consumer electronics products like CD players, DVD players, very fast access, high density hard disks, camera's, video systems etc. that at one hand achieve incredible performance in terms of accuracy, response dynamics, reproducibility and reliability and at the same time almost everybody can afford to buy today due to the low prices. The possibility to manipulate systems very fast and to virtually drive to steady state conditions that largely exceed the operating limits of the system make that the response characteristics of the system can be changed completely to make the system settle at desired operating conditions within a fraction of the natural response time of the system.

This possibility of very fast manipulation of the system also allows very accurate operation of the system and severe reduction of disturbances thus increasing the available dynamic range within which the system can be operated.

The component that has had a major impact on our society the past 50 years, the electronic transistor, today does not have an equivalent in the chemical processing industry. It is possible however to create an equivalent component. The basis for this component is to be found in catalysts and enzymes. Catalysts and enzymes both influence the status and progress of reactions in petrochemical, chemical and bio-chemical environments. Bottom line these components reduce the energy needed to make a reaction start or enable reactions to proceed at higher speed. The basic effect of these components on the progress of a chemical reaction is similar to the basic effect of a transistor on an electrical current, when it is operating at a given operating condition. Affecting the activity of the catalyst or the enzyme has a same impact on initiation or progress of a reaction as manipulation of the basis current or gate voltage has on the amount of current passing through the electronic transistor. Realizing manipulability of the catalyst or enzyme activity creates the "chemical transistor".

The "chemical transistor" device paves the way towards extremely responsive, very high performance operation of processes in the processing industries. It will enable operation of processes at demand in an extremely flexible and highly automated way. As an example the impact of the "chemical transistor" on a slurry loop polymerization process can be taken. Today's operation of this reactor is limited to the natural response dynamics of the process to realize process transitions between process grades. The resulting typical average transition time is approximately 4 hours for state-of-the-art industrial reactors. The "chemical transistor" applied in this process will enable a grade transition in seconds instead as a result of the potential to initiate a direct controlled swing to the operating conditions required for the new grade. As another example the conversion in a chemical reactor can be taken (e.g. NH ₃ synthesis, catalytic Cracking, Styrene production, etc.). Current reactor operation and today's applied use of catalysts often limits conversions to a fraction only of full conversion. Techniques like trickle bed operation already allow a significant increase of conversion per pass. Application of the "chemical transistor" will enable much larger conversions, depending upon the process, even up to 100% conversion in a single pass. The use of manipulable catalyst activity in a control loop enables operation of reactions at very tight specifications regarding conversions, heat production etc. Ultimately the application of the "chemical transistor" will take away the market restrictions felt in the European and North- American process plants today. It will enable operation of processes at productivity conditions that are multiples of today's. The impact on the market will be extreme as soon as the technology gets accepted and applied. The technology will enable development of completely new processes and process designs that can be operated at a fraction of the costs of today's processes.

The thrust of the present proposal is to transfer the concept of the transistor to the field of chemistry and improve the available bandwidth and control in small size chemical reactors. Doing so would open the perspective of unparalleled flexibility in operation as well as greater control over the fundamental processes at the heart of chemical processes, i.e. the catalytic surface. An important ingredient in this philosophy is the replacement of the usual thermal activation of chemical processes by smarter, dynamical activation methods.

Traditionally, there are four variables used to control chemical processes: temperature, pressure, concentration and residence time (see also above). In this application we aim to add a fifth degree of freedom: controlling the catalytic surface condition by smart activation. The direct local and dynamic influencing of the conditions at the catalytic sites, introduces a new and precise way of controlling reaction paths and their rates. This opens reaction pathways with involvement of reactive species in concentrations and configurations different than in the conventional steady-state approach of catalytic processes. Conventional reaction complexes that need or create excess heat in order to run can be replaced by alternatives that operate highly energy efficient by precise activation of molecular states. Two of the considered smart activation approaches are non-thermal activation (NTA) and microsecond temperature pulsing. Fast electrical current pulsing (< 10 ^~5 s) may temporarily create a very local temperature spike at reactive sites, which influences the reaction paths. With NTA accelerated electrons from field emission or surface plasma excite species locally and precisely and enable adsorption/reactions to take place on the catalyst. A closely related method that we propose is E-field pulsing to activate the catalytic surface in a way that is somewhat similar as in photo-catalysis.

For the actual methods to realize smart activation a variety of concepts is conceived. The central theme is to actively steer the energy levels at the catalyst surface. Three methods in particular are proposed: smart activation by temperature spikes, by surface plasma and by E-field pulses.

Temperature spikes are created by a pulsed current through a layer of catalyst. By precise dimensioning of the heat flows in the system, pulses of for example 1000 K in 10 ^"5 s are created. The precise values required depend on the specific catalytic reaction. This form of actuation is based on well-known electrical engineering techniques and can be realized quickly. An initial setup has been created to demonstrate the effects of quickly and locally applying energy in chemical reactors. Examples of non-thermal activation (NTA) are discussed below.

Pre-defined electron energies are created by dedicated pulsed non-thermal plasma at ambient pressure at the surface of the catalyst (surface discharge or field emission). The challenge is to accelerate electrons to the optimum energy level for the activation of excited states. The energy of these states has to be in the range of the energy required to overcome the barriers for chemisorption when the excited molecules strike the catalyst. Since the lifetime of many excited states of interest is short, the activation should occur at or near the surface of the catalyst.

Thirdly, E-field excitation is proposed, for the gas phase as well as for the solid-state catalyst. It is suggested that similar to the mechanism that occurs with photo catalysis by the transfer of photon energy, an E-fϊeld pulse delivers the energy to bring an electron across the band gap leaving a hole in the valence band. Local E-fϊeld strength and mobility of the electrons may determine the energy transferred to the free electrons created. The activation mechanism of reactants may subsequently depend on the efficient energy transfer by virtue of electron-to-electron impulse transfer. Catalytic materials containing P-type, N-type or PN junctions can be investigated for their effectiveness in creating electron-hole pairs that serve to initiate the reactions on the cat surface. Alternatively, an E-fϊeld pulse acting on the gas phase can shift the energy levels of the valence electrons of the gas molecules to enhance "dissociative bonding" between surface molecules and gas molecules. In comparison with the surface plasma, this third concept does not need ionization. This saves energy compared to the plasma activation technique (note however that with the plasma-activation technique, the electron, once created, can be used many times).

Since the new activation technique has the potential to greatly enhance chemisorption, the range of catalyst materials does not have to be restricted anymore to the traditional well adsorbing metals. Instead, the choice of catalytic material can be much widened and focused on e.g. optimum reaction and desorption properties.

Earlier work on plasma-assisted catalysis encountered a few major difficulties:

• Absence of precisely tuned activation

• Ineffective creation of radicals

• Weak contact between most of the plasma and the catalytic surface.

The present approach entirely circumvents these problems and is therefore incomparable with this older work. The invention is also distinct from so-called non-thermal plasma chemistry because it acts exclusively at the catalyst surface and it uses pre-defined energy and E-field. It is also far from microwave chemistry which is steady state and only proven to add heat.

The chemical transistor concept aims to precisely activate specific reactions in a reaction complex. The following reaction complexes have the main focus during the start of this invention. • Non-oxidative methane coupling: Methane activation requires high temperatures, while the hydrogenation runs better at low temperatures. The principle idea here is to stimulate methane adsorption by tuned energy pulses while allowing hydrogenation to take place in between the pulses.

• Fischer-Tropsch synthesis: Using syngas instead of methane makes it easier to create higher hydrocarbons, but still has great selectivity issues. By having a low base temperature, precise activation can allow to influence the product distribution.

• Polymerization: Here three reaction types are involved, initiation, propagation and termination. Experiments have indicated that the chemical transistor pulsing concept allows to trigger initiation reactions (i.e. the reaction in the test case with the largest activation energy), after which propagation can easily take place at low temperatures and with low chance of termination.

Control over the molecular weight distribution is what is aimed for in this reaction scheme.

Hence, in a first aspect, the invention involves a process for the production of a compound comprising:

a. providing a reactor with a reactor volume containing a catalyst on a support;

b. providing one or more starting products in the reactor volume while maintaining the reactor volume under non-reactive conditions for the one or more starting products (i.e. realized nominal reactor conditions are set to inhibit completion of the full reaction complex); c. subsequently providing (a short) energy pulse to the reactor volume, wherein the pulse contains sufficient energy to start, and especially enable completion of, a catalytic reaction of the one or more starting products to provide a reaction product comprising the compound; and

d. subsequently removing the reaction product from the reactor volume.

Hence, with a relatively short (single) pulse, designed to let the starting products react to the desired end product in the presence of the catalyst, the desired end product may be obtained. After the pulse, the reaction product is removed (from the active reaction volume), and new starting product may be introduced in the (said) reactor volume.

Preferably, at least one dimension of the reactor volume is selected from the range of

100 nm-500 μm. The term "dimension" relates to height, width, length and diameter, if applicable. The height of the reactor is calculated from the reactor surface. The area of the catalyst is calculated as the integrated area over the length and width (or diameter) over which the catalysts extends in the reactor. Hence, the term catalyst surface may especially relate to the surface over which the catalyst is applied. This may for instance be the substrate surface. When one or more dimensions like, height, width, length and diameter, if applicable, vary than the mean values may be taken. The term reactor volume especially relates to that volume of the reactor over the catalyst. Hence, if only part of a reactor comprises a catalyst, for the calculation of the volume only the dimensions in relation to that part of the reactor where the catalyst is applied are relevant. Especially, at least one dimension of the reactor volume is selected from the range of 10 μm-300 μm. More especially, the reactor height over the catalyst surface is selected from the range of 10 μm-300 μm. Hence, in an embodiment, a process and a micro reactor are suggested, wherein the reactor volume has a reactor height over a surface of the catalyst selected from the range of 10 μm-300 μm.

The conditions within the reactor volume are generally chosen that under nominal conditions, the desired reaction does not or does hardly occur. Further, the catalyst, such as a metal, a metal oxide, or an enzyme, is arranged at well defined positions within the reactor volume. A major difference with "process intensification" is that the energy used to bring valence electrons of the catalyst in the excited state, and thereby activation of the reactants to react, is done by well defined (and tightly controlled) energy input to the catalyst or reactants. The energy within the pulse is well defined and is adjusted to the energy needed to activate the starting products. The activated starting products react then to the desired end products. The energy provided to the active part of the reactor volume does thus directly lead to the reaction, which leads to a high efficiency. A good transport of the starting products and reaction product may therefore be of importance, because the reactions may, dependent upon the frequency of the energy pulses, proceed fast. Material transport is therefore adjusted to the reaction.

Now, it appears there is a fifth degree of freedom: the frequency and energy content of the pulses.

This degree of freedom may be of importance to provide well controllable and predictable processes. Due to the nominal non-reactive conditions, the reactions may be relatively safe. The reaction may not further be determined by the statistics of the velocity distribution of the molecules, but by well defined and targeted energy input at the catalyst.

Hence, the catalyst is activated by the energy, and the reaction may take place since the catalyst, due to the energy pulse, activates the starting products to react. The starting products may be chosen from the group consisting of gas and liquid. At the nominal conditions, one or more starting products may be introduced in the reactor volume. These one or more starting products may be gaseous at nominal conditions, may be liquid at nominal conditions or one or more may be gaseous and one or more may be liquid at nominal conditions. The term "nominal conditions" herein refers to the state wherein the reactor volume is between the energy pulses, i.e. in substantially non-reactive conditions for the starting product(s). The conditions are preferably set to inhibit at least one of the steps in the complete reaction complex. An inhibited reaction step is at demand activated by the applied energy pulse.

In a specific embodiment, the energy pulse has a pulse width in the range of 10 μs or less, such as 5 μs or less, like 1 μs or less, such as in the range of 0.1-10 μs. The energy pulse may also be a composed pulse, i.e. a pulse that has a pulse width wherein different energy amounts may be provided during subset times of the pulse width. For instance, a pulse of 1 μs might consist of a pulse having width of 500 ns, having a specific energy, followed by a pulse having also a width of 500 ns, having another specific energy.

The (sub) pulse width may also be smaller, such as in the range of about 5-500 ns. By choosing the pulse energy, specific pulse width and optional pulse composition, the desired product may be obtained, or may even be created step by step (composed pulse). In general, the (sub) pulse width may be larger than about 0.1 ns, such as equal to or larger than 1 ns.

In a further embodiment, the process further involves periodical repeating one or more times procedures b-d (see above). This will generally be the case.

The (repetition) frequency of the pulses may for instance be in the order of 0.01-50000 Hz, such as in the range of 0.1-5000 Hz, which may be "short" enough to relax to the nominal state, remove the reaction product and introduce new starting product(s).

Exemplary, the energy pulse has a pulse energy in the range of 0.01 - 500 mJ, like for instance 0.1-100 mJ. For instance, 0.01-500 mJ/cm ² catalyst surface may be provided per energy pulse.

In a first embodiment, the process involves providing heat pulses, respectively, as energy pulses. The catalyst (surface) is temporarily heated to provide the desired energy within the pulse width. In this way, the reaction products react to the desired intermediate or end product (effluent) (indicated as "reaction product"). The reaction product comprises the (target) compound, but may in addition also comprise other (undesired) compounds. Hence, the term "reaction product" may also refer to reaction product mixture". In another embodiment, the process includes providing a surface plasma (pulse) to provide the energy pulse. In yet another embodiment, the process involves providing a temporary electrical field (pulse) to provide the energy pulse.

Preferably, the active reactor volume is in the range of 1 μl- 1 1. For instance, the height over the catalyst surface may be small, but the catalyst may extend over a large length, thereby still creating a relative large reactor volume

In a specific embodiment, the reactor is a monolithic reactor comprising reaction volumes of 1 μl- 1 ml. Hence, here each reactor volume have its own dimensions, of which preferably at least one dimension of the reactor volume is selected from the range of 100 nm- 500 μm.

The catalyst may for instance be a metal surface, it may also be a metal oxide (surface), or a surface of a support with metal(oxide) sites on the surface. Alternatively, or additionally, the catalyst may also be an enzyme.

In a further aspect, the invention provides a micro reactor for performing a process (such as described above) for the production of a compound comprising:

a. a micro reactor volume comprising a catalyst on a support;

b. one or more controllable ports to the reactor volume, arranged to allow one or more starting products for the production of the compound enter the reactor volume and arranged to remove a reaction product comprising the compound; and

c. one or more energy pulses generator(s), arranged to (periodically) provide one or more energy pulses having a pulse width in the range of 10 μs or less, such as 1 μs or less and having an energy in the range of 0.01-500 mJ per pulse to the reactor volume.

Especially, the micro reactor may further comprise a controller arranged to control the one or more controllable ports and the energy pulse generator.

In a specific embodiment, the invention also provides the use of a micro reactor for performing a Fischer-Tropsch process wherein the micro reactor comprises :

a. a micro reactor volume comprising a catalyst (e.g. composed of iron, cobalt, nickel, ruthenium) on a support;

b. one or more controllable ports to the reactor volume, arranged to allow one or more starting products for the production of the compound enter the reactor volume and arranged to remove a reaction product comprising the compound; and c. one or more energy pulses generator, arranged to provide one or more energy pulses having a pulse width in the range of 10 μs or less and having an energy in the range of 0.01-500 mJ/cm ² catalyst surface to the reactor volume.

wherein preferably at least one dimension of the reactor volume is selected from the range of 100 nm-500 μm.

Brief description of the drawings

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

Figure Ia schematically depicts the general layout of the invention.

Figure Ib further gives an embodiment in which the catalyst reaction is controlled by (tightly controlled, periodically applied) pulsed-wise temperature control at the catalyst surface.

A general description of a second embodiment is shown in figure Ic, where the reaction is controlled by (tightly controlled, periodically applied) electromagnetic field pulses across the catalyst surface and the reaction volume. The third example reaction control mechanism given here is the plasma-controlled principle, outlined in figure Id.

Figure Ie gives an impression of the time scales involved in the catalytic reaction process.

Figures If-Ig schematically depict the dimensions of the reactor volume in a non- limited number of embodiments.

Detailed description

Figure Ia schematically depicts the general layout of the invention. The reactor 1 comprises a reactor envelope 2, with, for example, a first feed channel 3 for supply of reaction component 4 and optionally a second feed channel 5 for supply of reaction component 6. In addition the reactor is provided with a discharge channel 7 for discharge of reaction products 8. The feed and discharge channels may be provided with gates/valves for controlled supply and discharge of components and products. The reactor has a reactor volume 20. Inside the reactor volume 20 a catalyst carrier material 9 (herein also indicated as support) with catalyst layer 10 are mounted, adjacent to the reaction zone 11. The catalyst layer 10 can be energised by various means, for example by a dissipative electrical heating, electromagnetic wave energy, microwave, plasma, acoustic and thermo-acoustic and other radiation means (light, nuclear).

Operation of the chemical transistor will now be elaborated, by using a thermal activation principle, outlined in figure Ib for the oxidation of CO to CO ₂ , in an atmosphere of Carbon monoxide (CO), Nitrogen (N ₂ ), Hydrogen (H ₂ ) and Oxygen (O ₂ ). It is known that the objective reaction (O ₂ + 2CO→ 2CO ₂ ) is hard to accomplish, without the undesired side reaction (CO+H ₂ O^H ₂ +CO ₂ ; 2H ₂ + O ₂ → 2H ₂ O) to occur.

In this embodiment, the reactor volume 20 further comprises an activation layer 12, comprising a thin (thickness typically <200nm) electrical heating element. In this schematically depicted embodiment, the activation layer 12 is placed between the catalyst carrier 9 and catalyst 10. Further, the activation layer 12 is connected through a power line 13 to a pulse generator 14.

Prior to pulse-wise operation, the reactor 1 is brought into sub-critical conditions regarding pressure and temperature for the objective reaction (O ₂ + 2CO→ 2CO ₂ ) to take place. During operation, prior to each pulse, reactor feed CO, N ₂ , O ₂ and H ₂ are transported into the reactor volume 20 and positioned adjacent to the catalyst surface. This process step may for instance take 10-1000 ms (to reproducibly achieve the intentional inhibited state in the reaction zone). In the next process step, the activation layer 12 is pulse-wise energised, thereby bringing the catalyst layer 10 and adjacent reaction zone 11 at the desired temperature conditions for the catalytic reaction to initiate and take place. This activation process step is kept very short (order of magnitude of for instance 1 μs or less); sufficiently long for the chemical reaction to take place and yet short enough to suppress undesired side reactions (e.g. 2H ₂ + O ₂ → 2H ₂ O; CO+H ₂ O<→H ₂ +CO ₂ ). The energy required in this case typically is in the range of 0.1-5 mJ/cm ² . Typically the duration of the pulse is set to be short in relation to the dynamics involved with material supply to and from the reactor and in relation to the dynamics involved with overall energy transport to and from the overall reactor. After the chemical reaction process step, reaction products and other gases are discharged from the reactor and simultaneously a fresh load of components are fed into the reactor. After completion of this full reaction cycle the whole cycle may be intentionally repeated periodically.

Another example, using electromagnetic field activation is described in a more general sense (without a specific objective reaction scheme) in figure Ic. In this embodiment the reaction zone 11 adjacent to the catalyst is located between a first electrode 16 (for instance positioned between the catalyst carrier 9 and the catalyst 10), and a second electrode 17. The electrodes are connected to an electrical pulse generator 14 by means of connectors 13 and 18. In this example the electrical field (for instance up to 10 kV/mm) activates the catalyst reaction by directly exiting the valence electrons to a higher energy state (typically 0.1-10 eV, such as 0.5-10 eV), necessary for the reaction to take place. As in the previous example the pulse-wise excitation and chemical reaction takes place in a much shorter time span (< 10 μs) than the physical time scale necessary to transport and position the reaction components and reaction products.

Figure Id outlines a third activation principle, based on plasma generation at the catalyst surface. A low temperature plasma is generated at the surface of the catalyst 10, in the reaction zone 11, by means of an electrode grid 19, for instance arranged between the catalyst 10 and catalyst carrier 9. The electrode 19 is connected to a pulse generator 14 by means of connection 13. By energising the electrode by short pulses (such as in the order 0.1-10 μs, such as 1-10 μs), free electrons are generated at the catalyst surface, inside the reaction zone 11. These free electrons with energies typically in the range of 0.1 eV up to 10 eV, provide the activation energy for the molecules to react and result in the objective reaction. As explained above, energy may be transferred by efficient (free) electron-to-electron impulse transfer.

The aspect of timescale separation between chemical activation (reaction) process and physical transport process is further explained in figure Ie. In this time-intensity graph the process activation pulses are displayed in time (horizontal axis) and intensity (vertical axis). Pulses are generated at time interval 31 (=l/process-frequency), at duration 30 and at intensity 32. This figure illustrates the difference in activation -chemical- time scale (30) and physical time scale (31), a difference of at least one order of magnitude (factor 10) to several orders of magnitude will be applied. The difference is dominated by the -relatively short- time needed for a chemical reaction complex to complete (Pulse-width) versus the time needed for physical transport of mass and heat.

In all examples given, activation of the objective reaction takes place in a (chemical) time scale much shorter than the physical time scale associated with the transport and positioning of the reaction components and products. Furthermore, the activation energy is relatively small, compared to the total energy involved. These features constitute the main characteristics of the invention, having the objective to provide a catalyst chemical reactor that is energy efficient, compact and high yield. Figure 1 f schematically depicts a cross section of a reactor envelope 2, of which part is provided with a support 9. On top of the support, catalyst 10 is provided. The length over which the catalyst extends is indicated with reference 1. In this embodiment, this length is the same length as the length of the support. In principle, the catalyst 10 might also be provided on the wall of the envelope 2 directly. In such embodiment, the wall functions as support. The height over the catalyst 10 is indicated with reference h. Would the catalyst surface be very rough or curved or irregularly shaped, the mean height over the catalyst 10 may be used as height h.

Figure Ig schematically depicts a cross section of a reactor envelope, of which part is provide with support 9. By way of example, a rectangular cross section is assumed. Further, also the catalyst area is assumed rectangular (here in this embodiment on a rectangular support 9). The length over which the catalyst 10 extends is again indicated with reference 1, and the width over which the catalyst 10 extends is indicated with reference w. In this embodiment, the catalyst surface would simply be l*w. The height over the catalyst 10 is indicated with h. Hence, the reactor volume in this embodiment would be l*w*h.

A reactor was built with a height 250 of μm over the catalyst (for instance Pt). Pulses of 10 μs were applied, reaching peak temperatures over 2000 ⁰ C. In about 20 μs, the reactor temperature is again at the separately controlled nominal temperature in the range of about 140-300 ⁰ C. Catalyst was applied to a rectangular of about 4 cm ² , thereby providing a 4 cm ² area of catalyst surface. Pulses having an energy of about 0.5-2.5 mJ were applied (i.e. 0.125- 0.625 mJ/cm ² catalyst surface). The relax time of about 20 μs was used to realize material transport from the reactor volume (reaction product) and again into the reactor volume (starting product(s)). The larger the energy pulse, the higher the reactivity at the catalyst (for instance Pt) surface.

Specific embodiments, are described below (and numbered for the sake of clarity):

LA process for the production of a compound comprising:

a. providing a reactor with a reactor volume containing a catalyst on a support; b. providing one or more starting products in the reactor volume while maintaining the reactor volume under non-reactive (inhibited) conditions for the one or more starting products;

c. subsequently providing an energy pulse to the reactor volume, wherein the energy pulse contains an energy sufficient to start a catalytic reaction of the one or more starting products to provide a reaction product comprising the compound, wherein the energy pulse has a pulse width in the range of 10 μs or less; and

d. subsequently removing the reaction product from the reactor volume.

2. The process according to process embodiment 1, wherein the energy pulse has a pulse energy in the range of 0.01-500 mJ/cm ² catalyst surface to the reactor volume.

3. The process according to any one of the preceding process embodiments, comprising providing a repetitive heat pulse as energy pulse.

4. The process according to any one of the preceding process embodiments, comprising providing a surface plasma to provide the energy pulse.

5. The process according to any one of the preceding process embodiments, comprising providing a temporary electrical field to provide the energy pulse.

6. The process according to any one of the preceding process embodiments, wherein the reactor volume is in the range of 1 μl - 1 1.

7. The process according to any one of the preceding process embodiments, wherein the reactor is a monolithic reactor comprising reaction volumes of 1 μl - 1 ml.

8. The process according to any one of the preceding process embodiments, wherein the catalyst is an enzyme.

9. The process according to any one of the preceding process embodiments, comprising repeating one or more times procedures b-d.

10. A micro reactor for performing a process for the production of a compound

comprising:

a. a micro reactor volume comprising a catalyst on a support;

b. one or more controllable ports to the reactor volume, arranged to allow one or more starting products for the production of the compound enter the reactor volume and arranged to remove a reaction product comprising the compound; and

c. one or more energy pulses generator, arranged to provide one or more energy pulses having a pulse width in the range of 10 μs or less and having an energy in the range of 0.01-500 mJ/cm ² catalyst surface to the reactor volume.

11. The micro reactor according to reactor embodiment 10, further comprising a controller arranged to control the one or more controllable ports and the energy pulse generator. The term "substantially" herein, such as in "substantially flat" or in "substantially consists", etc., will be understood by the person skilled in the art. In embodiments the adjective substantially may be removed. Where applicable, the term "substantially" may also include embodiments with "entirely", "completely", "all", etc. Where applicable, the term "substantially" may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, including 100%. The term "comprise" includes also embodiments wherein the term "comprises" means "consists of.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

The devices herein are amongst others described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation or devices in operation.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "to comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The term "and/or" includes any and all combinations of one or more of the associated listed items. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The article "the" preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.