CA2504901C - Electrical heating reactor for gas phase reforming - Google Patents

Abstract

The invention concerns an electrical reactor (8) for reforming, in the presence of an oxidant gas, a gas comprising at least one hydrocarbon, and/or at least one organic compound, including carbon and hydrogen atoms as well as at least one heteroatom. Said reactor comprises: an enclosure, a reaction chamber provided with at least two electrodes (2, 4) comprising at least one conductive lining material (7) electrically isolated from the metal wall of the enclosure, at least one supply (1a) of gas to be reformed, at least one oxidant gas supply (1a), at least one outlet for the gases from the reforming (1b) and one electrical source (13) for powering the electrodes (2, 4) and resulting in generation of an electronic flux in the conductive lining (7) between the electrodes and in heating said lining (7).

Description

REACTOR WITH ELECTRIC HEATING FOR REFORMING
GAS PHASE
FIELD OF THE INVENTION

The scope of this invention lies in the use of electricity for the reforming of natural gas, gas organic hydrocarbons, light hydrocarbons or biogas, with a view to their conversion particularly in synthesis gas, that is to say in mixtures based in particular carbon monoxide, carbon dioxide and hydrogen that can be used, inter alia, for the production of basic chemicals such as than methanol and dimethyl ether. The present invention is moreover as a favorable option for the stabilization of greenhouse gas emissions.
greenhouse gas (GHG), in that the electrical reforming reactor subject said invention can be fed in particular by carbon dioxide (carbon dioxide consumption).

PRIOR ART
It has been known since 1834 that it is possible to produce a combustible gas mixture, called synthesis gas, composed of simple carbon monoxide molecules and hydrogen by high temperature reaction of coal with steam of water. This gas has been used for a long time for heating (city gas) so for the synthesis of commodities including ammonia and methanol, same as for the production of hydrocarbons (Fischer-Tropsch reactions).
Synthesis gas is still used as a chemical intermediate, but is produced primarily from natural gas, which over the years has substituted advantageously with coal (Fauvarque, X, the synthesis gas: De la chemical synthesis to electricity production, Info Chimie Magazine, n - April (2001), pp. 84-88).

2 In principle, all hydrocarbon products derived from fossil resources (coal, oil, natural gas, etc.) or biomass can be processed in synthesis gas. In general, steam reforming is used for light hydrocarbons (boiling points below 200 C) as one in found in natural gas. In the case of carbonaceous solids (coal, forest biomass, lignin, etc.) and heavy hydrocarbons (tars, oils the gasification technique and oxidation partial oxygen or air (Courty, P., Chaumette, P., Syngas: A
promising Feedstock in the Near Future, Energy Progress, vol. 7, No. 1 (1987) 1.0 pp. 23-30).

Natural gas is the most used raw material for the production of gas of synthesis. Methane (CH4), the main constituent of natural gas, is a very stable molecule and its use for chemistry, apart from a few particular reactions (such as chlorination), go through its conversion to gas of synthesis, which is generally carried out by steam reforming.

In the coming years we can expect a growth in consumption of synthesis gas because of increased demand from the chemical industry of a share and because of the growth prospects of the fuel market synthetic. Synthesis gases used as chemical intermediates are usually generated at the place of production of a given end product. The consumption growth of synthesis gas requires use growing processes or systems for generating syngas.
One of the most well-known applications of synthesis gas is in the production of methanol. This is a basic chemical product produced at very large volume. Methanol is used primarily for the production of formaldehyde, itself a chemical intermediate, and acetic acid.
methanol can be considered an acceptable fuel with a power Higher Heating Calorific value (PCS) of 22.7 MJ / kg. In fact, being liquid at the ambient temperature, it has great potential for use as

3 synthetic fuel since it can easily be transported and stored (Borgwardt, RH, Methanol Production from Biomass and Natural Gas as Transportation Fuel, Ind. Eng. Chem. Res, vol. 37 (1998) pp. 3720-3767). The methanol can be used as a mixture in gasoline or even used directly as automotive fuel. It can also be used as fuel for heater. Finally, methanol has great potential for use in the energy systems with fuel cells, and more particularly in Polymer Electrolyte Fuel Cell (Allard, M., Issues Associated with Widespread Utilization of Methanol, Soc. Automot. Eng. [Spec. Publ.] SP-1505 (2000) pp. 33-36).

Today, methanol is mostly made from natural gas. The Natural gas sources are abundant. Rightly, we can consider the methanol as a gas transformation vector allowing eventually bring the vast reserves of natural gas to different markets of use of energy. In this context, the widespread use of methanol as fuel could allow indirect introduction of natural gas in the transport market.

Synthetic gas production accounts for nearly 60% of production of methanol. This demonstrates the preponderance of the process of production of synthesis gas in the manufacture of the final product. The process Traditional steam-based reforming is known to have a energy efficiency of 64% according to the PCS of methane (Allard, M., Associated with Widespread Utilization of Methanol, Soc. Autoinot.
Eng. [Spec. Publ.] SP-1505 (2000) pp. 33-36) with joint production of carbon dioxide as a by-product. In fact, part of the material first, natural gas, is transformed in the process. It's for this part of the carbon initially present in the gas. natural found in the form of CO2 released into the atmosphere.

4 In theory, it is possible to produce gaseous mixtures based on monoxide carbon and hydrogen, by a process of partial oxidation of methane such as illustrated by the following well-known reaction:

CH4 + 1/2 O2 - CO + 2 H2; OH = -36 kJ / mole (1).

According to this reaction, a gaseous product with a molar ratio is obtained H2 / CO of 2. This reaction can be put to use for the synthesis of the methanol. The reaction (1) is exothermic: it releases globally 36 kJ
of energy per mole of methane converted instead of requiring it. This quantity energy is low compared to the heating value of methane less than 800 kJ per mole of methane).

However, the approach that resides in steam reforming has been preferred. At the base, this reforming occurs according to the reaction:

CH4 + H2O (g) -3 CO + 3H2; AH = 206 kJ / mol (2).

This reforming reaction is highly endothermic. The amount of energy involved in the reaction (2) corresponds to almost 25% of the power calorific lower methane. Reforming on its own produces a gas with a H2 / CO molar ratio of 3. This is the reason why, in a plant of methanol production relying on reforming, one must see to balance the mixture by increasing the proportion of CO with respect to H2. To do this, we often uses the following reaction, called the reaction of gas to water ( Water Gas Shift), adding C02 to the mixture:

CO 2 + H2 - CO + H 2 O (g); AH = 41.2 kJ / mole (3) Under reaction (3), CO 2 is converted to CO and there is consumption hydrogen.

WO 2004/04142

5 PCT / CA2003 / 001689 Despite the disadvantages already mentioned, steam reforming remains the preferred reaction for the conversion of synthesis gas to light hydrocarbons in general. This is for two reasons: (i) eliminating the use of oxygen and (ii) avoid formation of carbon (soot). The training 5 free carbon is known to cause many problems of operation in the reactors, particularly with regard to the use of of catalytic reactors. Table 1 summarizes the benefits and disadvantages related to each of the two approaches.

Table 1 Comparison between traditional reforming techniques and partial oxidation Approach Advantages Disadvantages proposed Reformatting = Safe Process = Hydrogen Surplus - Recourse to water vapor = reaction of gas to water for thrust in swing the ratio H2 / CO
CO / H2 mixture = strongly endothermic reaction Oxidation = Reaction = Soot Formation partial exothermic = Use of pure oxygen required = H2 / CO ratio better balanced The use of both types of reforming may be considered integrated for the production of a better balanced mixture. So, we can put take advantage of the energy released by partial oxidation to meet the needs energy from an endothermic reforming process.

To help balance the composition of the synthesis gas intended for production of methanol, gaseous reactants were used. So, to help

6 reduce the H2 / CO ratio, we can use gas injection carbonic acid in the reaction medium so as to carry out the reaction next :
CO2 + CH4 - CO + H2; AH = 247 kJ / mole (4) This reaction is also endothermic, but it can be contribution to balance the H2 / CO ratio required for the production of the methanol. To achieve this, we can adjust the proportion of CO2 and steam of water in the feed of a reforming process according to the scheme following reaction:

CH4 + x CO2 + y H2O + energy -3 w CO + z H2 (5) Such a reaction presents very interesting perspectives of use on the environmental plan since it suggests the establishment of a process relying on the use of carbon dioxide as a raw material, which is known as one of the main greenhouse gases.

Reforming in the presence of water vapor and / or carbon dioxide is a Chemical transformation process that requires a supply of energy. On the thermodynamic plan, it is necessary A temperature higher than 700 C for the Reactions (2) and (4) can occur. The required energy can be provided by the combustion of natural gas itself. In this case, we burn some of the gas in a separate compartment of the reactor and heating is used by contact with a wall.

Thus, the reforming of natural gas is generally carried out in reactors chemical tubes containing a catalyst. These catalysts are found usually in the form of a powder or granules made of nickel on support based on alumina. The tubes containing the catalyst consist of a alloy resistant metal (eg nickel-chromium alloy) to corrosion and heat and are assembled in a shell and tube design. Reforming

7 produced inside the tubes filled with catalysts, while the heating takes place from outside the tubes, but inside the shell. Typically, operating conditions are for a temperature varying from 750 -850 C under a pressure of 30 to 40 atmospheres.

As an alternative to indirect combustion heating, it is possible to envisage use of heating based on electrical energy. The use of energy electric as a source of heat instead of heating by gas combustion naturalness provides considerable benefits, particularly with regard to ease of control and the ability to design compact reactors and Modular. Electricity is a form of energy that is easy to control because can have a quick and direct control over the flow of electrons to use in a given process. In addition, it is known that with electricity, one can provide a lot of thermal energy inside reduced volumes. The use of electricity. offers opportunities for using compact reactors, modular, high performance and high energy efficiency.

Another important point is the environmental aspect. When electricity comes from a non-fossil resource, we can consider in place of reforming processes without net emission of carbon dioxide. We can even consider setting up a process that is a net consumer of C02. Carbon dioxide is a combustion gas that can be recovered from flue gas from incineration processes or industrial processes.

There are many ways to directly use electricity as a source of energy for carrying out thermochemical reactions such as reforming.
It is a question of processes specially adapted to the treatment of mixtures gas with methane and other hydrocarbons in the presence of gas carbonic acid and / or water vapor. To help a reforming process, electricity can be used to:
to provide electrochemical work by the use of force electromotive (electric fields);

8 - ionize gases, which allows the generation of chemical species such that free radicals and ions that are known to have an effect catalytic on chemical reactions;
- provide heat by Joule effect; and induce electric currents in a material.

Among the main types of reactors with direct use of electricity, we electrochemical reactors (high temperature electrolysis), thermal plasma, cold plasma and ohmic heating.
Electrochemical reactor Natural gas reforming can be achieved through a process electrochemical relying on the use of a conductive electrolyte anion oxygen (O-). The ionic conduction of these electrolytes is carried out by a mechanism of leaps of oxygen vacancies that are positively charged. We can therefore use this type of material to perform pumping electrochemical oxygen atoms to achieve partial oxidation of a hydrocarbon. With this approach, air can be injected directly in the cathode compartment of the electrolytic cells. Under the action a electric field and a chemical potential gradient one can do in kind that there is a flow of oxygen passing through the solid electrolyte (in the form of of anions) to finally end up in the anode compartment in order to make it react with methane (or natural gas).

The most well known oxygen ion conductive material is zirconia stabilized with yttrium. This product is already on the market for manufacturing of oxygen probes. Moreover, it is already used for the construction of prototypes fuel cells type SOFC (Solid Oxide Fuel Cell). In general, high temperatures of the order of 600 to 1000 C are required for the material is sufficiently conductive ('e>0,05'n -lcm 1).

9 The use of an electrochemical reactor with ceramic electrolyte is mentioned in the works of Stukides (Stukides, M., Chiang, PH, Alqahtany, H. Nonoxidative Methane Coupling and Synthesis Gas Production in Solid Electrolyte Cells, Symposium on Natural Gas Upgrading II, San Francisco, April 5-10 (1992), ACS, The Division of Petroleum Chemistry Preprints, vol. 37, No. 1, pp. 261-268) who experimented with partial oxidation of methane with the addition of water vapor (allowing prevention of training of carbon) using, inter alia, iron electrodes. These works on the synthesis gas have shown that under certain conditions, pumping electrochemical oxygen allows the conversion of natural gas into a mixture of carbon monoxide and hydrogen.

PCT International Publication No. WO 00/17418 (Pham, AQ, Wallman, PH, Glass, RS, Natural Gas-Assisted Steam Electrolyzer, PCT Publication WO 00/17418 (2000)) proposes a different approach based on the use of an oxygen transport electrolyte. This approach combines high temperature electrolysis of water vapor and oxidation partial of a hydrocarbon. The method makes it possible to reduce by at least 65% the electricity consumption compared to traditional electrolysers. The overall reaction is equivalent to that of steam reforming.
next this process, there is hydrogen production on the cathode side and there is production of CO / H2 mixtures on the anode side.

The concept of partial oxidation by means of a controlled flow of oxygen passing through the wall of an oxygen conducting ceramic electrolyte anionic is already known, but much remains to be done to optimize performance of these ceramic membranes. In particular, attention must be paid to their mechanical strength under severe temperature conditions and their chemical resistance. A know-how has been developed in recent years sure Solid Electrolyte Fuel Cells (SOFC) and many teams work on the subject. At present, such membranes are not still available for applications requiring large areas like this would be required for the production of syngas.

The arc plasma reactor Arc plasma means a DC electric arc or alternative between two electrodes through which a gas is circulated (called gas plasma). It accelerates and produces a jet of gas containing material ionized. Traditional arc plasma is part of thermal plasmas and can be used for heating purposes especially in applications requiring of

10 high power densities. The jet in question is characterized by a level of very high temperature (above 3,000 K). As a result we have of a source of radiant heat which can be put to use for the rapid heating of different products, including gas mixtures. The arc plasma can be used for direct heating and dissociation of starting reagents such as methane and water vapor. Note that the presence of ionized material and the emission of ultraviolet radiation that one found in a plasma, can help catalyze several reactions chemical. The use of arc plasma in compact reactors intended for decentralized generation (energy systems in a user) is proposed by Bromberg (Bromberg, L., Cohn, DR, Rabinovich, A., Plasma Reformer-Fuel Cell System for Decentralized Power Applications, Int. J.
Hydrogen Energy, vol. 22, No. 1 (1997) pp. 83-94).

In the tradition of industrial processes, there is the Hüls process which has already been used on a large scale since 1940 for the production of acetylene go light hydrocarbons with reactors with a power of 8 to 10 MW. By getting Based on this long experience, the Hüls process has been adapted to achieve the reforming natural gas in the presence of CO2 or water vapor. We will find in the publication of Kaske, G., et al. (Kaske, G., Kerker, L., Müller, R., Hydrogen Production by the Plasma Hull-Reforming Process, Hydrogen Energy Progr. VI, vol. 1 (1986) pp. 185-190), a description of the use of Hüls technology for synthesis gas production. The reactor resides

11 in the use of two tubular electrodes cooled with water, the tube anode being connected to the mass. The gaseous reactants are injected tangentially and this gas movement makes sure that the electric arc is forced to slide in the direction of the gas flow. In this way, we have a controlled influence on the movement and position of the arc strike points in the electrodes, this who stabilizes the arc. If the flow of gas changes, the length of the arc and the voltage are modified which influences the power generated when the current is maintained constant.

The advantages of a plasma reforming process lie in the following:
- it empires the use of catalysts;
the reforming process can be carried out with a low ratio H2O / carbon, which avoids unnecessary heating of water vapor for to carry out the reforming;
- removal of sulfur is not necessary (sulfur is known to poison conventional reforming catalysts based on nickel); and - the process is modular and offers the possibility of small units Flexible.
However, the main disadvantage of such an approach lies in the cost investment and the use of electrical power transformation.

The sliding arc reactor An electric arc process as a generator of active species to catalyze reforming in particular is proposed by Czernichowski (Czemichowski, P., Czernichowski, A., Conversion of Hydrocarbons Assisted by Gliding Electric Arcs in the Presence of Water Vapor and / or Carbon Dioxide, US Patent United States 5,993,761 (1999); Lesueur, H., Czernichowski, A., Chapel, J., Electrically Assisted Partial Oxidation of Methane, Int. J. Hydrogen Energy, flight. 19, No. 2 (1994) pp. 139-144; Fridman, A., Nester, S., Kennedy, LA, Saveliev, A., Mutaf-Yardimci, O., Gliding Gas Arc Discharge, Progess in Energy and Combustion Science, vol. 25, No. 2 (1999) pp. 211-231). next

12 this approach, electric shocks produce chemical species (electrons, ions, atoms, free radicals, excited molecules) as well as than photons that can strongly catalyze direct conversion.
Czernichowski proposes the use of gliding arc formed of electric arcs sliding along two divergent electrodes with respect to each other, enter which circulates a gas at high speed (> 10 m / s). The sliding bow goes to near the place between the two electrodes where the distance is the most low, and extends by sliding progressively along the electrodes in the direction of the flow until it goes out; at the same time, a new discharge is formed at the original place. The path of the discharge is determined by the geometry of the electrodes, the flow conditions, and the characteristics of the electricity supplied. This displacement of points of discharge on uncooled electrodes prevents the establishment of an arc permanent and resulting corrosion.
Fridman et al. (Fridman, A., Nester, S., Kennedy, LA, Saveliev, A., Mutaf-Yardimci, O., Gliding Gas Arc Discharge, Progess in Energy and Combustion Science, Vol. 25, No. 2 (1999) pp, 211-231), show a theoretical discussion on the use of a gliding arc. It mentions the operating principles and proposed applications for the technology.
Czernichowski presents a review of the state of the art regarding the use of the plasmas and electric arcs for reforming (Czernichowski, P., Czernichowski, A., Device with Plasma from Mobile Electric Disc.
its Application to Convert Carbon Matter, PCT Publication No. WO 00/13786 (2000)). The above-mentioned PCT International Publication No. WO 00/13786 a new generation of slid-arc reactor called G1idArc-II. In the new concept, one of the electrodes is mobile and is powered by a mechanical movement.

One of the interesting features of the gliding arc technology is the that the electrodes can be made of ordinary steel. Another' advantage related to technology is the ability to power such a reactor with

13 a wide range of gas compositions. The gliding arc technology can be used for reforming in the presence of CO 2 and / or steam of water. It can also be used to achieve partial oxidation at oxygen (or air enriched with oxygen). Since partial oxidation does not require thermal energy as such, electricity is then basically used to help speed up the thermochemical process by catalytic pathway by the generation of active species.

The gliding arc technology is a simple technique and which has been successfully tested in the laboratory. However, this technology involves the use of power electronics for the transformation of the current to obtain the conditions required for the deployment of arcs while ensuring that there are no disturbances on the network Power.

The cold plasma reactor Thermal plasmas can concentrate large amounts of power in small volumes but a large amount of energy is needed to be able to heat the gases at very high temperatures. An approach alternative to the use of thermal plasmas is the use of plasmas cold, that is to say a plasma generated in out-of-equilibrium conditions thermal, which produces ionized species without significant heating.
Some of the technologies include some of the approaches experimented in the laboratory: corona discharges, electrical pulsations and microwave plasmas. The use of cold plasmas generated by landfills crown in the reforming of mixtures composed of combustible gases (hydrocarbons or alcohols) in the presence of oxygen and / or water vapor is described in the patent application of the French Republic No. 2,757,499 (Etient, C., Roshd, M., Hydrogen Generator, Patent Application of the French Republic No. 2,757,499 (1996)).

14 The ohmic heating reactor The ohmic heating reactor relies on the use of electricity essentially as a source of heat generated by direct conduction or by induction. As the passage of a current through a resistor generates heat, such resistance can take the form of a bed of particles heated through which circulates the gas to be treated.

A known application of ohmic heating by direct conduction is the use of a fluidized bed of Joule-heated coke pellets for the hydrocyanic acid (HCN) synthesis from methane (CH4) or propane (C3H8) mixed with ammonia (NH3) (Shine, NB, Fluohmic Process for Cyanide Hydrogen, Chem. Eng. Progress, vol. 67, No. 2 (1971) pp. 52-57).

The concept of induction-heated packing is mentioned in the patent of United States No. 5,362,468 for a pyrolysis application (Coulon, M., Boucher, J., Process for Pyrolysis of Fluid Effluents and Corresponding Apparatus and U.S. Patent No. 5,362,468 (1994)). This process aims at the treatment of liquid halogenated organic compounds. It is presented here as a concept relying on the ohmic heating of a lining, concept that can be applied gas treatment. In this process, the effluents to be treated are heated by contact with a stack of solid elements providing a surface area contact area of at least 10 m2 / m3. These elements are typically used under the shaped balls of 10 to 150 mm in diameter and are heated by induction electromagnetic or by electrical conduction. The elements in question may be made of an electrically conductive material covered with a refractory material. Among the conductive materials, we can find the graphite and conductive ceramic carbides. For materials refractory, mention is made of graphite, refractory metals, oxides ceramics, carbides, borides of metals, etc.

At the base, ohmic heating by direct conduction is presented as the easiest way to use electrical energy in case we have use of alternating current at the standard frequency of the supply network electric (60 Hz in North America, 50 Hz in Europe).

The small reactor and compact reactor As the study of the prior art reveals, there are several types of systems of reforming, whether it is catalytic or non-catalytic reforming at the water vapor (Steam Reforming, SR), by partial oxidation (POX), by auto-thermal reaction (ATR) or a combination of these techniques. The traditional processes for the production of hydrogen by reforming or oxidation 10 partial are large scale processes long established in the petrochemical industry. With the recent craze of fuel cells for residential and automotive use, there is a significant investment of the effort on the development, testing and commercialization of new reformers more and more compact. The fight to grab a share of the

15 market is very intense. Elements patented by current firms concerning so-called compact reformers targeting the residential or transport are subtle. They mainly address treatment methods (sequence flow, arrangement of parts, injection modes) or materials such as advanced catalysts that can increase the performance of small reforming units. The references cited below give an overview of the main elements claimed in compactness of reactors conventional reforming.

The UOBTM reformer is a small to medium hydrogen generator hydrogen capacity (10 to 800 m3 / h) coupled to a hydrogen purifier, and intended to be installed on a fixed site. This technology can be used in upstream of all low capacity applications using pure hydrogen as reagent or fuel (metallurgy, glass industry, hydrogenation, electronics, chemistry, etc.). The basic patent of UOBTM technology (Under Oxidized Burner) refers to a device aimed at converting a hydrogen fuel in a non-catalytic burner, which will be possibly mixed with another part of the fuel to reduce the

16 emission of nitrogen oxides from gas engines' (Greiner, L., Moard, DM, Emissions Reduction Systems for Internai Combustion Engines, Patents United States No. 5,207,185 (1993)). The following patents concern improvements in the technology in question: Moard, D., Greiner, L., Apparatus and Method for Decreasing Nitrogen Oxide Emissions from Internai Combustion Power Sources, United States Patent No. 5,299,536 (1994); Greiner, L., Moard, DM, Bhatt, B., Underoxidized Burner Utilizing Improved Injectors, U.S. Patent No. 5,546,701 (1996); Greiner, L., Moard, DM, Bhatt, B., Shift Reactor for Use with an Underoxidized Burner, U.S. Patent No. 5,728,183 (1998); Greiner, L., Woods, R., Reduced Carbon from Under Oxidized Burner, US Patent No. 6.089.859 (2000).

For its part, the patent, issued in the United States under the number US-B1-6.207.122 deals with a process combining partial oxidation (POX) and steam reforming (SR), to form what is called a auto-thermal process (ATR) (Clawson, LG, Mitchell, WL, Bentley, JM, Thijssen, JHJ, Method for Converting Hydrocarbon Fuel into Hydrogen Gas and Carbon dioxide, U.S. Patent No. 6,207,122 BI (2001)).
Each of these processes is performed in respective concentric tubes.
The two effluents are directed and mixed in a catalytic reforming zone to produce hydrogen.

Other patents show steam reforming systems on example, the following documents: Primdahl, II, High Temperature Steam Reforming, U.S. Patent No. 5,554,351 (1996);
Rostrop-Nielsen, J., Christensen, PS, Hansen, VL, Synthesis Gas Production by Steam Reforming Using Catalyzed Hardware, US Patent United States 5,932,141 (1999); Stahl, HO, Reforming Furnace with Internal Recirculation, U.S. Patent No. 6,136,279 (2000).

17 In addition, the following patents relate to auto-thermal processes with Catalysts: Christensen, TS, Process for Soot-Free Preparation of Hydrogen and Carbon Monoxide Containing Synthesis Gas, US Patent 5,492,649 (1996); Primdahl, II, Process for the Preparation of Hydrogen and Carbon Monoxide Rich Gas, U.S. Patent No. 5,958,297 (1999);
Christensen, PS, Christensen, TS, Primdahl, 'II, Process for the Autothermal Steam Reforming of a Hydrocarbon Feedstock, US Patent United States No. 6,143,202 (2000); Dybkjaer, I., Process and Reactor System for Preparation of Synthesis Gas, U.S. Patent No. 6,224,789 B1 (2001).

Finally, the patents mentioned below refer to appliances incorporating the hydrogen separation:

= Edlund, DJ, Pledger, WA, Steam Reformer with Internal Hydrogen Purification, United States Patent No. 5,997,594 (1999): Device compact steam catalytic reformer comprising a system of separation and internal purification of hydrogen, in addition to a system integrated heating by residual gases after separation of hydrogen;

= Edlund, DJ, Hydrogen-Permeable Metal Membrane and Method Producing the Healthy, U.S. Patent No. 6,152,995 (2000): Method for the preparation of metal membranes permeable to hydrogen;

= Edlund, DJ, Hydrogen Production Fuel Processing System, Patent United States No. 6,221,117 BI (2001): patent for improving the patent of United States No. 5,997,594;

= Verrill, CL, Chaney, LJ, Kneidel, KE, Mcllroy, RA, Privette, RM, Compact Multi-Fuel Steam Reformer, US Patent n 5.938.800 (1999): compact model of a catalytic steam reformer of water with internal separation of hydrogen and recovery of energy gas not completely converted.

18 Technical problem to solve In reforming applications, the catalysts used are based on metals and are usually prepared by impregnation of very small quantities of metal on the surface of a very large porous support. Often catalysts are attached to a support of alumina (Al 2 O 3), silica (SiO 2), zirconia (ZrO 2), alkaline earth oxides (MgO, CaO), or a mixture of them. Among the most well-known catalysts are platinum and nickel. The best known catalysts for reforming are expensive materials. It is desirable to use these metals in a form highly dispersed on an inert carrier so as to expose the reagents a largest possible fraction of the atoms of this catalyst.

Thus, the use of electrically heated reactors the use of traditional catalysts, does not appear as a solution economic. Electricity is a noble source of energy and its use in as a source of energy must have economic benefits undeniable.
At present, we do not know reforming devices of hydrocarbons based on an ohmic heating principle and not involving the use of traditional catalysts.
The gas percentages are all by volume.

The present invention is a completely new approach to production of synthesis gas from light hydrocarbons as found in the natural gas or biogas. Biogas is a mixture of combustible gas produced during fermentation of various organic materials. It consists usually in volume of 35 to 70% of methane, 35 to 60% of gas carbonic acid, 0 to 3% hydrogen, 0 to 1% oxygen, 0 to 3% nitrogen, from 0 to 5% of various gases (hydrogen sulphide, ammonia, etc.) and steam of water.
The invention aims in particular at:

19 = substantially reduce the conversion costs of the gases to be reformed into introducing the use of simple, easily available materials on the market and very inexpensive;
= eliminate problems related to the use of traditional catalysts;
= make optional the preliminary desulfurization of the reagents; and = set up modular, compact, high efficiency reactors and very flexible of use.

BRIEF DESCRIPTION OF THE FIGURES
Figures la to lh illustrate the results of simulations 1 to 8 respectively, which come from kinetic calculations related to methane reforming.

Figure la gives the results of the kinetic calculations related to the reforming of the methane according to simulation 1 for a CH4 / H2O ratio of 1 mole / 1 mole; a temperature of 1,000 K, a pressure of 1 atmosphere and without catalyst.

Figure lb gives the results of the kinetic calculations related to the reforming of the methane according to simulation 2 for a CH4 / H2O ratio of 1 mole / 1 mole; a temperature of 1,000 K and a pressure of 1 atmosphere.

Figure 1c gives the results of kinetic calculations related to reforming of methane according to simulation 3 for a CH4 / H2O / CO2 ratio of 1 mole / 1 mole / 0.333 mole; a temperature of 1,000 K and a pressure of 1 atmosphere.

Figure ld gives the results of kinetic calculations related to reforming of methane according to simulation 4 for a CH4 / H2O ratio of 1 mole / 2 moles;
a temperature of 1,000 K and a pressure of 1 atmosphere.

Figure 1e gives the results of kinetic calculations related to reforming of methane according to simulation 5 for a ratio CH4 / H2O / 02 of 1 mole / 2 moles / 0.25 moles; a temperature of 1,000 K and a pressure of 1 atmosphere.

Figure lf gives the results of the kinetic calculations related to the reforming of the methane according to simulation 6 for a CH4 / H2O / CO2 ratio of 1 mole / 2 moles / 0.333 moles; a temperature of 1,000 K and a pressure of 1 atmosphere.

Figure lg gives the results of kinetic calculations related to reforming of methane according to simulation 7 for a ratio CH4 / H2O / 02 of 1 mole / 2 moles / 0.5 moles; a temperature of 1,000 K and a pressure of 1 atmosphere.
Figure lh gives the results of the kinetic calculations related to the reforming of the methane according to simulation 8 for a CH4 / H2O ratio of 1 mole / 3 moles; a temperature of 1,000 K and a pressure of 1 atmosphere.

Figure 2 shows a reforming reactor according to an embodiment of the invention, wherein the electrodes are in the form of hollow discs perforated.
Figure 3 shows a typical front view of an electrode with orifices and protuberances.

Figure 4 shows a reactor with electrodes in the form of solid discs.
Figure 5 illustrates the case of tangential injection and radial injection of the gas in a reactor according to one embodiment of the invention.

Figure 6 shows an arrangement of electrodes connected in parallel.

Figure 7 shows an arrangement of electrodes connected in three-phase (top view of a cut in a cylinder).

Figure 8 illustrates the general arrangement of the laboratory reactor, in which TC stands for thermocouple.

Figure 9 shows a photograph of the output electrodes (left) and inlet (right) of the laboratory reactor, in which the length of reference is the thumb.
Figure 10 shows the scheme of the test bench using the reactor of laboratory; in this figure P means pressure measurement, R means regulator, T means temperature measurement, TC means thermocouple, Ts means temperature at the outlet of the reactor, Te means temperature at the inlet of the reactor reactor, Tm means temperature in the middle of the reaction chamber. F1 represents a gas meter.

SUMMARY OF THE INVENTION

The present invention relates to an electric reactor for reforming, in presence of an oxidizing gas, a gas comprising at least one hydrocarbon, optionally substituted, and / or at least one organic compound, optionally substituted, containing carbon and hydrogen atoms and at least a heteroatom. This reactor comprises as structural elements:
- a thermally insulated enclosure;
a reaction chamber provided with at least two electrodes and located at inside the enclosure, said reaction chamber comprising at least a conductive lining material, the lining in question being electrically isolated from the metal wall of the enclosure so as to avoid any short circuit;
at least one gas supply to be reformed;

at least one supply of oxidizing gas, distinct or otherwise from the feed in gas to reform;

at least one exit for the gases resulting from reforming; and an electrical source enabling the electrodes to be energized and resulting in the generation of an electronic flux in the lining conductor between the electrodes and in heating said lining.

Another aspect of the invention is a process for reforming a gas comprising at least one optionally substituted hydrocarbon, and / or at least one a optionally substituted organic compound having carbon atoms and hydrogen and at least one heteroatom, comprising contacting the gas to reforming with an oxidizing gas in a reaction chamber, characterized in that than :
the reaction chamber contains a conductive packing material forming part or all of a reforming catalyst, the material being placed between electrodes;

the electrodes are energized to produce an electric current continuous or alternating generating an electronic flux in the lining.

GENERAL DEFINITION OF THE INVENTION

The term reforming as used in the context of this invention is relating to a thermochemical reaction of conversion of a hydrocarbon or a organic molecule in synthesis gas, which is a gas mixture in particular at base of hydrogen, carbon monoxide and carbon dioxide.

22a The term gas as used in the context of the present invention is advantageously relating to a compound or a mixture of compounds which present in the gaseous state at a pressure preferably neighboring the pressure atmospheric temperature and at a temperature below 200 Celsius.

The term hydrocarbon as used in the context of this invention is relating to one or more molecules containing only carbon and hydrogen.

The term organic compound as used in the context of this invention relates to one or more molecules whose elements constituents of the molecular structure are carbon and hydrogen as well as one or many heteroatoms such as oxygen and nitrogen.

The porosity index as used in the context of this invention is relating to the proportion of bulk volume of a material that is not occupied over there solid portion of said bulk material. The vacant space between the particles '1 1 solids, your cavities on the surface and inside the particles as well as the volume openings and holes present through the material contributes to the porosity.
A first object of the present invention is constituted by a reactor for the reforming, in the presence of an oxidizing gas, of a gas comprising at least one hydrocarbon, optionally substituted, and / or at least an organic compound, optionally substituted, having carbon and hydrogen as well as at least one heteroatom.

1 o This reactor comprises;
= an enclosure, preferably thermally insulated, and more preferentially still thermally insulated from the inside;
a reaction chamber provided with at least two electrodes and located at inside the enclosure, said reaction chamber comprising at least a conductive packing material and defining in whole or in part a refitting catalyst, the lining in question being insulated electrically from the metal wall of the enclosure so as to avoid any short circuit;
at least one gas supply to be reformed;
at least one supply of oxidizing gal, whether or not distinct from food or gas, to reform;
at least one exit for reforming gases; and an electrical source for energizing the electrodes and resulting in the generation of an electronic flux in the lining conductor between the electrodes; and éYentuellemetst - at the hands a supply of heat in the lining. advantageously heat input, which can come from outside or inside the filling can be carried out by any appropriate means and preference may result from the generation of the electronic flow in the packing.

A particularly interesting subfamily of reactors according to the invention is consisting of those having at least one of the following characteristics;
a reaction chamber which is parallelepipedal in shape cylindrical;
at least one of the electrodes is of the hollow type and constitutes the port of the gas to be reformed.

(MAA

CA 02504901 2005-05-04, '1 = r at least one of the electrodes is of the hollow type and constitutes a gas supply duct for reforming and oxidizing gas;
at least one of the electrodes is of the hollow type and constitutes the outlet gases resulting from reforming i at least two of the electrodes are located opposite one another.

According to another advantageous embodiment of the reactor of the invention, this last, comprises at least two metal electrodes each tubing and perforated hollow disc, said disc is located at the end of the tube opening into the reaction chamber and is in contact with the packing the reaction chamber to supply the power supply electric filling and heating Joule effect.

The conductive packing material is preferably selected from the group constituted by the elements of group VIII of the Periodic Table (CAS numbering) and alloys containing at least one of those elements, preferably the lining is selected from the group consisting of the materials having at least 80% of one or more of said Group VIII elements, more preferably still in the group consisting of iron, nickel, the cobalt, and alloys containing at least 80% of one or more cMs elements, more advantageously still the lining is iron-based or a of its alloys and preferably it is selected from the group consisting of the carbon steels. Advantageously the conductive packing material defines all or part of a catalyst of the reforming reaction previously defined.

A particularly interesting subfamily of reactors is incorporated the reactors in which the material has in the dense state a resistivity electric current, measured at 20 C which is preferably between 50 x 10.9 and 2.000 x 10'9 ohm-m, more preferably between 60 x 10 -9 and 500 x 10's ohm-in, and more advantageously still between 90 x 10-9 and 200 x 10'9 ohm-m, For example, the filling consists of elements of the material ~ 5 driver in a form selected from the group consisting of straws, the fibers, filings, sintered, balls, nails, threads, filaments, wool, rods, bolts, nuts, washers, chips, powders, grains, granules, and perforated plates.

The filling material may also be constituted, in whole or in part, by perforated plates and the surface percentage of the openings in the plate is between 5 and 40%, and even more preferably between 10 and

20%.

Very economically, the lining material is steel wool soft, for example a mild steel wool marketed under the trademark BullDog and manufactured by Thamesville Metal Products Ltd. (Thamesville, Ontario, Canada).
According to another advantageous mode making it possible to increase the efficiency of the reactor, The packing material is pretreated to increase the least one following characteristics - the specific surface - the purity ; and - the chemical activity.
This pretreatment can be a mineral acid treatment and / or thermal.

According to two other specific variants:
the conductive lining consists of fibers having a diameter Characteristic of between 25 m and 5 mm, more preferably still between 40 m and 2.5 mm, and still more preferably 50 m and 1 mm, and a length greater than 10 times its diameter characteristic, more preferably greater than 20 times its diameter characteristic and more advantageously still greater than 50 times its characteristic diameter; or the conductive lining defining a porous medium has a surface area of more than 400 m2 of exposed area per cubic meter of reaction chamber, preferably more than 1,000 m2 / m3, more more preferably more than 2,000 m2 / m3.

A particularly interesting variant is the reactors in the packing consists of balls and / or yarns based on at least a Group VIII element or at least one metal oxide, preferably based on iron or steel.

It should be noted that the gas supply duct to be reformed can be positioned at different locations of the reactor, it can for example be positioned perpendicular to the direction of the electronic flow created between electrodes.
According to two other positioning variants:
when the reaction chamber is of cylindrical shape, at least one of the supply ducts of gaseous mixture, consisting of the gas to be reformed and / or oxidizing gas, is positioned tangentially to the wall cylindrical reaction chamber; or at least one of the reformed gas outlets is positioned in the reaction chamber opposite the gas supply.
The electrical source supplying the reactors of the invention is constituted by a current transformer in the case of a power supply type alternating current (AC) or a current rectifier in the case of a power supply type DC (DC), which source electric is of a power calculated according to the energy needs of the reactions of concerned reforming, which obey the laws of thermodynamics, and said power source to provide a minimum current intensity calculated by the following equation:

Iminimum -% = F
in which: Iminimum is the minimum current to be applied, expressed in Amperes;

1 is a parameter that depends on the geometry of the reactor, the type of packing, the conditions of operation and gas to reform; and F is the molar flow rate of the gas to be reformed, expressed as mole of gas to be reformed / second.

The parameter X is established experimentally by varying the current at ugly a variable intensity source (AC or DC) and also by varying the flow rate gas to reform. X depends on the geometrical characteristics of the reactor considered, the geometry and the nature of the lining, and finally the terms of reactor operation (compositions and flow rates of the gases supplied, temperature and reaction pressure). Typically the value of a, is better than C / mole.

It should be noted that the current to be fed into the lining can be produced by electromagnetic induction in the sense that one can realize a transformation of current through the use of localized inductors around the chamber of reaction.
Thus, the lining itself can be confused with an electrode.

The conductive lining has a preferably understood porosity index between 0.50 and 0.98, more preferably between 0.55 and 0.95, and more preferentially still between 0.60 and 0.90.

Moreover, the residence time of the reagents (gas to be reformed) is preference greater than 0.1 second, more preferably greater than 1 second, and more preferentially still greater than 3 seconds.

According to another variant, the lining of the reaction chamber is consisting wool made of steel wire mixed with shape materials spherical such as balls made of steel.

Moreover, a particularly interesting variant is constituted by the reactors, in which the reaction chamber contains, in addition to the conductor, non-conductive and / or semiconducting and / or insulating electrically, such as ceramics and alumina, these are then suitably arranged in the reaction chamber so as to adjust the overall electrical resistance of the lining.

As an illustrative example of electrodes particularly adapted to be present alone or in several units in the reactors of the invention, we may mention perforated type electrodes having a diameter opening of more than 25 micrometers, the holes being more preferably evenly distributed at a density of not more than 100,000 openings per cm2 electrode surface.

We can size the holes so that the pressure drop due to the gas flow through electrode or electrodes does not exceed 0.1 atmosphere.

In a preferred embodiment, the openings are distributed over the surface of the perforated electrode so as to ensure uniform diffusion of the gases through of the reaction chamber and or the size of the openings increase in the meaning radial electrode or perforated electrodes (s).

According to a particularly effective variant, at least one of the electrodes is such that its face exposed to the lining is provided with protuberances and / or projections, which are preferably of conical shape and, more preferentially still in the form of a needle.

The protuberances and / or protrusions can be dimensioned so that their spacing density corresponds, in a preferential mode, to more than 0.5 unit per cm 2 of electrode.

The length of the protuberances and / or protrusions can in turn vary enter 0.001 and 0.1 times the length of the lining of the reaction chamber, and the width of these protuberances and / or projections may vary between 0.001 and 0.1 the diameter of the electrode disk.

As an illustration, the projections are of conical shape, the cones corresponding being preferably dimensioned so that the ratio of the height of the cone on cone diameter is at least 1, more preferably this ratio is greater than 5 and even more preferably said ratio is better than, 10.

Advantageously, the reactors of the present invention can be sized to fit into the previously mentioned category so-called "compact", "portable" or "portable" reactors.

A second object of the present invention is constituted by a method for gas reforming of reacting the gas to reform in presence of at least one oxidizing gas, in an electric reforming reactor according to the first object of the present invention.

According to an advantageous embodiment, the method comprises at least the following steps of:
a) preparing, inside or outside the reforming reactor, a mixing the gas to be reformed and the oxidizing gas;
b) contacting the mixture obtained in step a) with the lining of the reaction chamber, preferably by passing through an electrode dig ;
c) application of an electronic flow for energizing electrodes of the reaction chamber;
d) heating the packing of said reactor by the electronic flow at a temperature allowing catalytic transformation of said mixture gaseous; and e) recovering the gas mixture from the reforming, preferably by passage in another hollow electrode.

Advantageously, steps c) and d) are carried out before step b) and the bedroom Reaction is preheated prior to supplying the gas to be reformed and oxidizing agent, at a temperature of between 300 ° C. and 1,500 ° C. under an atmosphere inert such as nitrogen, by the prior completion of step c).

The electrical method of the invention is advantageously used for the Gas reforming consisting of at least one of the compounds of the group consisting of by C1 to C12 hydrocarbons, optionally substituted in particular by the the following groups: alcohol, carboxylic acid, ketone, epoxy, ether, peroxide, amino, nitro, cyanide, diazo, azide, oxime, and such halides than fluoro, bromo, chloro, and iodo, which hydrocarbons are branched, not Branched, linear, cyclic, saturated, unsaturated, aliphatic, benzene and aromatic compounds, and advantageously have a boiling point of less than 200 C, more preferably a boiling point below 150 C, and more preferentially, a boiling point of less than 100.degree.

The hydrocarbons are preferably selected from the group consisting of:
the methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane, each of these compounds and linear or branched form, and mixtures of at least two of these compounds.

The method gives very good results when used for the reforming natural gas, in particular for gas reforming initially containing of sulfur and having already undergone a treatment to remove sulfur, of preferably to advantageously reduce the sulfur content below 0.4%, more preferably below 0.1%, and still more preferably Below 0.01%, the percentages being by volume.

When treating natural gas containing sulfur, some or all of the totality of packing reacts with the sulfur present in the gas to be reformed and the part of packing thus used is called sacrificial packing.

Among the gases that can be reformed by the process of the invention, also mentions the biogas coming in particular from the fermentation anaerobic of various organic materials. These biogases are advantageously consisting in volume of 35 to 70% of methane, 35 to 60% of carbon dioxide, 0 to 3% hydrogen, 0 to 1% oxygen, 0 to 3% nitrogen, 0 to 5%
of various gases such as hydrogen sulphide, ammonia and water vapor.

As a preferred example, the gas to be reformed is a natural gas constituted of 70 to 99% methane, accompanied by 0 to 10% ethylene, from 0 to 25%
ethane, 0 to 10% propane, 0 to 8% butane, 0 to 5%
hydrogen, 0 to 2% carbon monoxide, 0 to 2% oxygen, 0 to 15% nitrogen, 0 to 10% carbon dioxide, 0 to 2% water, 0 to 3%
one or more C5 to C12 hydrocarbons and traces of other gases.

For the advantageous implementation of the process, the oxidizing gas is constituted at least one gas selected from the group consisting of carbon dioxide, carbon monoxide, water, oxygen, nitrogen oxides such as NO, N20, N205, NO2, NO3, N203, and mixtures of at least two of these components, preferably the mixtures of carbon dioxide and water.

According to another variant, the gas to be reformed consists of at least one of the compounds of the group consisting of structural organic compounds molecule whose constituent elements are carbon and hydrogen, so one or more heteroatoms such as oxygen and nitrogen, advantageously to understand one or more functional groups chosen in the group consisting of alcohols, ethers, ether-oxides, phenols, aldehydes, ketones, acids, amines, amides, nitriles, the esters, oxides, oximes and preferably having a boiling less than 200 C, more preferably a boiling point lower than 150 C, and even more preferably a boiling point lower than 100 C.

Preferably, the organic compounds are methanol and / or ethanol.
According to another advantageous variant, the gas to be reformed can also contain one or more gases of the group consisting of hydrogen, nitrogen, oxygen, water vapor, carbon monoxide, carbon dioxide, and gases inert group VIIIA of the Periodic Table (CAS numbering), or mixtures of at least two of these.

Particularly interesting results in reforming are obtained when the gas mixture fed into the reaction chamber contains less 5% by volume of oxygen.

As an illustration, the mixture of the gas to be reformed and the oxidizing gas is consisting 25 to 60% methane, 0 to 75% water vapor and 0 to 75%
carbon dioxide, preferably 30 to 60% methane, 15 to 60% of water vapor, and 10 to 60% carbon dioxide, and more preferably still 35 to 50% methane, 20 to 60% water vapor and 10 to 50%
of carbon dioxide.

According to another preferred embodiment, the mixture of gas to reform and gas oxidant is, in a preferred embodiment, about 36.0% methane, and the oxidizing gas is about 49.0% water and about 12% water.
carbon dioxide.

The parameters of the gas supply are chosen so that the report Atomic carbon / oxygen molar in the gas mixture fed into the reaction chamber is between 0.2 and 1.0, preferably this ratio is between 0.5 and 1.0, and even more preferably said ratio is between 0.65 and 1.0.

Step c) is performed using an alternating current (AC) or continued (DC) modulated according to the temperature level to be maintained in the reactor, preferably continuously avoiding stops and applying only Moderate changes to the intensity of the current.

According to a preferred variant, steps b), c) and d) are carried out at a level temperature range between 300 and 1500 C, preferably in a range between 600 and 1000 C, and even more preferentially in a range between 700 and 900 C.

In steps b), c) and d), the pressure in the reaction chamber is advantageously greater than 0.001 atmosphere and is preferably between 0.1 and 50 atmospheres, more preferably still it is between 0.5 and 20 atmospheres.

The pressure profile is advantageously kept constant in the reaction chamber during reforming.

The process of the invention can be carried out continuously, preferably when one uses a long-life and discontinuous packing material, preferably for a period of at least 30 minutes, when using a low-life material, that is to say which is consumed quickly at Classes of the reforming process. The lining is then replaced or regenerated between two periods of implementation.

It has also been found that the reforming reaction appears catalysed by micro-arcs jumping between the particles of the packing or by sites activated by the accumulation of charges on the surface of the packing particles and / or by the passage of electric current.

According to an advantageous embodiment of the invention, the lining conductor is chosen so as to have a porosity index included enter 0.50 and 0.98, more preferably between 0.55 and 0.95, and more preferentially still between 0.60 and 0.90.

The residence time of the reagents is preferably greater than 0.1 seconds, more preferentially greater than 1 second, and more advantageously still greater than 3 seconds.
According to another preferred embodiment, the process is carried out with a reactor in which, for at least one of the electrodes, the perforations are distributed evenly with a density of not more than 100,000 openings per cm 2 of electrode area and said openings are such that the pressure loss due to the passage of gas through the electrode or electrodes does not exceed 0.1 atmosphere.

As an illustration of preferential implementation, mention may be made of the process for the reforming of hydrocarbons and / or organic compounds, reacting them in the presence of an oxidizing gas (from preferably in the presence of water vapor and / or carbon dioxide and / or other gas) in a reaction chamber containing:
1) a metal-based conductive lining defining a porous medium having a surface area of more than 400 m2 of exposed surface area m3 of the reaction chamber, this packing serving both as a medium of heating and catalysis medium; and 2) two metal electrodes each consisting of a tubing and a perforated hollow disc in contact with the lining to achieve supplying the electric current required for heating this Joule effect filling and to help with movement catalysis electrons;
comprising the following steps:

a) mixing the hydrocarbons and / or the organic compounds and the gas oxidant;
b) introducing the mixture of step a) into the reaction chamber by injection into one of the electrodes;
C) contacting the mixture of step a) with the packing;
d) the application of an electronic flow by energizing the electrodes of the reaction chamber;
e) heating the lining by the electronic flow and producing a movement of electrons to help catalyze 10 supply of an electric current by the two electrodes, this current being such that it passes directly into the lining; and f) evacuation and recovery of the reactor gas by passage through the other electrode.

Advantageously, these process parameters are applied for reforming methane, consisting of reacting the latter in the presence of carbon and water vapor, in a reaction chamber of a volume available of 322 cm3 containing:
1) a conductive lining consisting of 50 g of steel wool, for example 20 BullDog type steel wool manufactured by Thamesville Metal Products Ltd (Thamesville, Ontario, Canada) defining a porous medium, which medium consists of alternating layers of 1 cm thick said steel wool adequately compacted; and 2) two metal electrodes made of carbon steel made 25 each of a tubing about 30.48 cm long and a disc hollow of a diameter of about 6.35 cm, which disk is perforated, provided with protruding so as to ensure a good contact with the lining;
comprising the following steps:
a) mix the gaseous reactants, which are methane, 30 carbon and water vapor, according to respective concentrations approximately 39%, 12% and 49.0%;

b) introducing the mixture of step a) into the reaction chamber by injection into the input electrode;
c) contacting the mixture of step a) with the packing;
d) application of an electronic flow by energizing the electrodes of the reaction chamber, which flow is obtained by a current continuous electric with an intensity of about 150 amperes;
e) heating of the lining by the electronic flow at a temperature about 780 C and production of an electron movement allowing to assist in catalysis by supplying an electric current two electrodes, this current being such that it passes directly into the packing; and f) evacuation and recovery of reactor gas by passage through the output electrode, which gas consists of hydrogen, monoxide of carbon, oxygen, methane and carbon dioxide, following concentrations of approximately 69%, 28%, 0,4%, 1,7% and 0.9%, established on an anhydrous and standardized basis.

Another particularly interesting example is a process for the reforming of hydrocarbons and / or organic compounds, reacting the latter in the presence of an oxidizing gas (from preferably in the presence of water vapor and / or carbon dioxide and / or other gas) in a reaction chamber containing:
1) a metal-based conductive lining defining a porous medium having a surface area of more than 400 m2 of exposed surface area m3 of the reaction chamber, this packing then serving as both medium heating and catalytic medium; and 2) two metal electrodes each consisting of a solid disk contact with the lining to achieve power supply required for heating this Joule effect lining and to help catalyzed by electron movements;
comprising the following steps:

a) mixture of hydrocarbons and / or organic compounds and gas oxidant;
b) introducing into the reaction chamber the mixture of step a) by injection at the radial or tangential openings of the reaction chamber;
c) contacting the mixture of step a) with the packing;
d) application of an electronic flow for energizing electrodes of the reaction chamber;
e) heating of the lining by the electronic flow and production of a electron movement to help catalyze by the supply of an electric current by the two electrodes, this current being such that it passes directly into the lining; and f) evacuation and recovery of the reactor gas by axial flow, tangential or radial with axial, radial or tangential.

As an advantageous example, the use of the process of the invention for methane reforming consists of reacting the latter in the presence of dioxide of carbon and water vapor, in a reaction chamber of a volume available 26.5 liters containing:
1) a conductive lining consisting of steel filaments defining a porous medium, which medium consists of filaments each of which is a length of about 1 cm and a diameter of about 0.5 mm; and 2) two metal electrodes made of carbon steel made each of a stem about 50 cm long and a disc of one diameter of about 15 cm, which disc is provided with projection so as to ensure good contact with the packing;
comprising the following steps:
a) mixture of gaseous reactants, which are methane, carbon and water vapor, according to respective concentrations about 53%, 17% and 30.0%;

b) introducing into the reaction chamber the mixture of step a) by injection at the radial or tangential openings present in the reaction chamber;
c) contacting the mixture of step a) with the packing;
d) application of an electronic flow for energizing electrodes of the reaction chamber, which flow is obtained by a DC electrical current of about 500 amperes;
e) heating of the lining by the electronic flow at a temperature about 780 C and production of an electron movement allowing to assist in catalysis by supplying an electric current two electrodes, this current being such that it passes directly into the packing; and (f) evacuation and recovery of reactor gas by passage through radial outlet openings, which are located at the end of the reaction chamber, and which gas consists of hydrogen, carbon monoxide, oxygen, methane and carbon dioxide, following respective concentrations of approximately 69%, 28%, 0.4%, 1.7% and 0.9%, established on an anhydrous and standardized basis.

In these advantageous modes previously mentioned, the residence time of the reagents is preferably greater than 0.1 second, more preferably greater than 1 second, and more preferably still greater than 3 seconds.
A third object of the present invention is constituted by the use a or multiple electric reactors for:
(i) the production of syngas used in particular for methanol production, and preferentially for implantations with electricity consumption from 1 to 5 MW;
(ii) the recovery of energy and / or chemicals from the biogas generated by landfills;

(iii) the production of hydrogen for road transport fuels, for example for the supply of automobiles and buses; and (iv) the production of hydrogen for so-called applications portable or stationary, as an example for supply of fuel cells intended for residences and road vehicles.

The electrical method of the invention can advantageously be used for:
(i) the production of syngas used in particular for methanol production, and preferentially for implantations with electricity consumption from 1 to 5 MW;
(ii) the recovery of energy and / or chemicals from the biogas generated by landfills;
(iii) the production of hydrogen for road transport fuels, for example for food automobiles and buses; and (iv) the production of hydrogen for so-called applications portable or stationary, as an example for battery power. fuel for residences and road vehicles.

A particularly interesting use of the process is found in the desulfurization of sulfur-containing gases.

EXPLANATORY THEORY OF THE PRESENT INVENTION

This section presents an operating model of the invention. She shows that a material as common as iron can have a catalytic effect on reforming reactions, that this material does not need to be in the form traditional commercial catalysts, and can be used surprisingly in a form with simple geometry allowing its use as a means for providing ohmic heating. It has been discovered that this material, in a porous form, is conducive both for the heating of reagents and for the catalysis of reforming reactions.

Kinetics of reaction Group VIII metals in the periodic table (CAS numbering) have good catalytic activity for reactions involving the formation of hydrogen and the cracking of hydrocarbons, these reactions 10 explain in part by the contribution in forming links Chemicals their orbitals d partially filled. Iron, cobalt, nickel, Ruthenium and osmium are the most active metals in the group in question.
These metals are known to be easily oxidizable in the presence of water or oxygen and easily reduced thereafter in the presence of hydrocarbons or Other reducing gases. The metal allows you to tear off the water (and also C02) oxygen atoms and then relay them to hydrocarbons while forming metal oxides which are easily reduced to the conditions of synthesis. This is used to catalyze reforming reactions. In industry, nickel is by far the most widely used known catalyst for realize the 20 reforming natural gas.

Palladium, iridium and platinum, also of group VIII, absorb easily the CO but hardly allow its release. As for metals Zn, AI and Cu groups IB, IIB and IIIB, these are moderately active.
The least expensive and most readily available metal known is iron.
he is electrically conductive but offers some electrical resistance necessary for ohmic heating, accentuated by the granular structure of the bed catalytic it forms. The kinetic behavior of iron in reactions of Steam and / or C02 reforming was calculated from a model mathematics that we developed in order to make predictions about the catalytic activity of certain metals by following the oxidation state of the catalyst, as a function of time, under the reforming conditions. This model, proved to be consistent with the laws of thermodynamics, and it allows to simulate the formation of carbon-carbon likely to be precursors to carbon formation solid (soot, coal, heavy hydrocarbons, etc.).

To quantify the kinetic behavior of a metal, the Eley-Rideal model has been used. This one suggests that a reaction could occur directly following a collision of a gaseous species on a molecule or fragment of adsorbed molecule (identified by an asterisk *) that is to say:

A + * B - products (6) whose reaction rate (rj) is described by the following equation form :

rr = kd PA OB (7) where PA is the partial pressure of species A in the gas phase, OB is the proportion of active sites covered by the molecule or fragment B, and kk is here specific reaction rate.

The results of the simulation indicate that thermodynamic equilibrium be reached in 3-6 seconds in the case of methane reforming in the presence of steam or a mixture of water vapor and CO2, even with a very small amount of iron. Although the reaction time is much larger than the catalysts generally used make it possible to achieve 0.02 seconds), iron can be considered as a cheap material allowing the catalysis of reforming reactions.

The following paragraphs present highlights related to the calculations of kinetics of methane reforming reaction with steam and / or C02 in the presence of iron as a catalyst. The graphs presented in Figures at lh present the results of calculations of the modeling on the evolution of each of the chemical species, as a function of time, in the case of several calculation scenarios. All these simulations were performed using the iron as a catalyst (which is initially considered as an oxide ferrous, FeO), with a quantity corresponding to 0.01 mole of iron per mole of methane in the diet.

Simulations 3 and 6 (Figures 1c and 1f respectively) were carried out at go initial mixtures to approach a gas composition desirable for the production of methanol. A parameter used to characterize the composition of the synthesis gas intended for the production of methanol is defined by the following ratio:

R = (nx2 - nco2) / (nco + nco2) (8) where nH2, nc02 and nco represent respectively the molar proportion of H2, CO2 and CO in the synthesis gas. The value of R must be in the neighborhood of 2 in the case of the synthesis of methanol. Simulations 3 and 6 refer to a case of reforming methane with CO2 and water vapor. Comparing the results of simulations 3 and 6, we observe that adding a little steam water has the effect of promoting a better conversion of methane (there is no practically more methane after 2 seconds according to Figure lf) and also to increase the molar ratio H2 / CO. This illustrates that it is possible in playing with the supply of reagents, to produce gas mixtures having a composition adjusted to the stoichiometry of a given product.

Simulations 1, 2, 4 and 8 (Figures la, lb, ld and lh respectively) resident in the study of steam reforming. Surprisingly no reaction occurs in the absence of catalyst (Figure la). In comparing Figures lb and ld, we see that the addition of water vapor favors a better conversion of methane. In the case of Figure lb, we compute after 2 seconds a residual amount of 0.2 moles of methane per mole of methane fed, whereas in the case of Figure 1d, there is virtually more residual methane after 2 seconds.

Comparing simulations 4 and 8 (Figures Id and lh respectively), we see the addition of excess water vapor has the effect, above all, of increasing the CO 2 content. Indeed, water vapor promotes the reaction of gas to water.
In the case of Figure 1 d, we obtain after 2 seconds a production of 0.25 mole of CO2 per mole of methane fed, while in the case of Figure 1 h, 0.4 mole of CO2 is obtained after 2 seconds per mole of methane fed.
Looking at the results of simulations 5 and 7, we can see than the addition of oxygen results in a decrease in the hydrogen content, a decrease in CO content, as well as an increase in CO2. adding Oxygen, even in the presence of water vapor, has the effect of generating unsaturated molecules considered precursors of carbon (formation undesirable soot).

As shown in FIGS. 1b to 1h, iron makes it possible to adequate catalysis of reforming reactions. In most of the cases, the thermodynamic equilibrium is practically reached in the space of 3 to 6 seconds at atmospheric pressure in the case of a temperature of 1000 K
with as little as 0.01 mole of iron per mole of methane fed. This last parameter has proved to be extremely important since it is at the heart of the present. invention. A priori, the proportion of catalyst required for the reaction is low and an amount corresponding to 0.001 mol / mol gives results similar modeling. However, when the amount of catalyst bECOMES
too small, the diffusion phenomena become important making the websites metal assets less available for reaction and it follows that the reaction rates decrease under equation (7).
In the context of the development of the present invention, it has been established that the reaction can be catalyzed by a sufficient amount of iron chemically active corresponding to 0.01 mol / mol, the iron then being in metallic form or oxidized. Indeed, in all cases of reactions studied, the balance between the iron metal and its oxidized state FeO is reached almost instantaneously. By example, if we consider the reaction of gas to water, we obtain the quantities following moles (mole of product per mole of CO 2 fed), after 1ms = H2: 0.54 mole;
H 2 O: 0.46 moles;
= CO: 0.45 moles;
= CO2: 0.55 moles;
= CH4: 0.0015 moles;
= Fe: 0.0021 moles; and = FeO: 0.0079 moles.

Catalyst surface and general features of the invention Iron is not expensive and it is not obligatory to use it under a form comparable to the forms used for the manufacture of catalysts traditional.
In the case of the present invention, it is proposed instead to use the iron under a coarser form, but that allows to use it both as a medium of heating, as an electrical conductor and as a catalyst. With such approach, even if we rely on a catalytic effect accentuated by the passage of electrical current and / or the local accumulation of electrical charges at the area particles of the packing, one exempts from the use of the catalysts or the traditional preparation of these. We have to however aim at adequate shaping to expose the iron atoms to reagents but without having to use this metal in highly dispersed form.

In the case of the present invention, iron is used in the form of a metal packing having a porous medium having a surface adequate exposure of metal to gaseous reactants. We are talking preferably a fixed bed that will be heated by Joule effect thanks to an ohmic heating, which will be obtained by the passage of electric current (electronic flow) realized using electrodes in contact with the lining. This lining is contained in a thermally insulated container at the entrance of which gaseous reactants are introduced and at the exit of which the gaseous products are evacuated. This 5 packing is characterized by:
= the required catalysis surface;
= the required reaction volume;
= the apparent porosity of the reaction medium constituted by the packing;
= the geometrical characteristics of the lining; and 10 = electrical resistance of the lining.

In theory, a small amount of iron is required to achieve the reaction at condition the gas / catalyst contact is sufficient (well mixed systems). he is the amount of catalyst that must be distributed in the reaction volume in To form the contact surface required to effect the reaction. We speak here a surface exposing the iron atoms to the reagents. The internal volume of the reaction chamber of the reactor is preferably of cylindrical form when the electric current is emitted between two electrodes. This volume is filled with a lining consisting of iron-based unitary elements, which 20 then constitutes the packing, the bed or the porous medium.
Preferably, the minimum required surface of iron to catalyze the reaction must be better than 744 m2-s / mole of methane (744 m2 / (mole / s) of methane). In addition, the report between the catalyst surface and the reaction volume (empty fraction of volume packing or porosity) should preferably be greater than 560 m2 / m3.
25 Such a ratio is achievable using iron in forms geometric simple (eg, steel wires, powders, etc.). For example, we can obtain this in the case of very long filaments of 0.75 mm diameter constituting a packing defining a bed with a porosity of 0.9 (ratio of volume empty and bulk volume of the packing). We can play on the diameter of 30 strands, on the amount of filaments and compaction of the packing.
Good Of course, other geometric shapes can be used for the elements units to form the lining. This includes, but not limited to, of the granules, grains, powders, filings, filaments, wools, of the fibers, threads, straws, marbles, stems, nails, washers, sintered, perforated plates, irregularly shaped pieces such as of the shavings, bolts and nuts or any mixture of different forms.

The lining is intended to form the heating medium by passage of current through the latter (Joule effect) thanks to the electrical properties of the material of the lining and the possibility of production of micro-arcs electric.
So, we make sure that the heat source does not come from the phase gas but catalytic packing itself. take in account the surface densities mentioned above, the heat transfer flux between the packing and the gaseous medium is selected at less than 100 W / m2-K. this is low in the case of devices operating at more than 700 C, due to the flux of heat by radiation. Direct heating of the catalyst in these terms of operation ensures that the maximum temperature of the catalyst and close to the target temperature in the reaction medium.

In addition to the direct heating of the catalyst by Joule effect, effects catalytic can be supported and induced not only because of the material constituting the catalyst, but also through increased availability and mobility of electrons and / or by the formation of micro-arcs in the porous medium. Finally, in the present invention, the current flow (electronic flow) to through filling is essential to maintain chemical activity and properties catalytic material constituting said lining.

DETAILED DESCRIPTION OF PREFERENTIAL MODES OF
THE INVENTION

The reactor described in the present invention relies on the use of a filling constituting a porous medium formed of metal compounds and / or their oxides. Preferably, the packing consists of particles of small dimensions based on iron or steel. This includes, but is not limited to, filaments, wool, threads, straws, fibers, filings, sintered, powders, grains, granules, balls, stems, nails, bolts, nuts, chips, washers, perforated plates, or other regular or irregular shapes allowing the generation of a structure porous material promoting gas flow and dispersion and having a sufficient contact area with the reagents. Figures 2 and 4 illustrate the proposed configuration. Said figures show a profile view of a metal cylinder inside which one has a thickness of refractory (for also of electrical insulation) and also a thickness of thermal insulation (for also electrical insulation). This cylinder contains the lining which is confined between two metal electrodes (which may be steel). The reagents to which are in the form of a gaseous mixture and are injected simply inside the porous structure defined by the lining.

The packing must have the following characteristics:

= have a porosity and geometric characteristics allowing a residence time of the gaseous reactants sufficiently high, at least 0.1 second, and preferably 3 seconds, to guarantee a degree sufficient advancement of the reaction;

= have sufficient surface area for contact between gaseous reactants and the packing both to catalyze the reaction and to heat the reagents so as to maintain the temperature level required by the reaction, preferably 744 m 2 / s / mole of methane;
= ensure constant electrical contact between the two electrodes; and = present a porous structure allowing the establishment of micro-arcs electric.

Figures 2 and 3 show a preferred arrangement for which the electrodes consist of perforated plates through which pass the gas. These plates may be provided with protuberances to assist a better current dispersion and better contact between the lining and the electrodes. Figure 3 shows a front view of the disc of an electrode with a typical arrangement that can be considered. The arrangement of the openings electrodes must ensure a uniform flow of gases in the reactor and avoid stagnant areas. The openings will be distributed preferably at a density corresponding to 0.5 openings per cm 2 of area. The diameter of these openings must be such that the pressure drop across the discs does not exceed 0.1 atmosphere. Note that the layout of the openings and protuberances can be modified to modify the profile flow and dispersion of gases inside the lining. It is not not mandatory that these arrangements are uniform.

The electrodes must be in permanent contact with the lining properly compacted. The aforementioned protuberances have precisely to help maintain the electrical and mechanical contact enter the packing and the electrode. Preferably, these protuberances are formed of spikes. A minimum number of spikes corresponding to a density of 0.5 peak per cm2 of disk area is recommended and these peaks are uniformly distributed on the surface of the electrode. The size of these tips can be variable. It is proposed a diameter that can vary between 0.001 and 0.1 times the packing diameter (bulk volume of the packing medium) and a length between 0.001 and 0.1 times the length of the volume (in bulk) packing.

Preferably, the electrodes have similar geometries although they may be different. The electrodes are preferably manufactured in iron, nickel or alloys based on these metals. In this case, these participate in the reaction, since they have surfaces metal having a catalytic effect. Moreover, by making sure that the electrodes they-they are used in the transport of gases, we promote a better dispersion of the heat that can be produced at the level of electrodes. We try to make sure that the lining and the electrodes reservoirs constitute a heating medium with a temperature level that be as homogeneous as possible.

Figure 4 shows a variant of the embodiment presented by the Figure 2. In this case, the electrodes are not perforated but the gases circulate perpendicularly and close to each of the electrodes, using openings which are preferably in radial position. In the facts, many openings also distributed on the circumference of the reactor allow a adequate dispersion of both the supplied and the outgoing gases (Figure shows only one opening for each of the electrodes). In addition, these openings should be as close as possible to each of the electrodes.
In the case of the two configurations shown respectively by the Figures and 4, the reactor is advantageously provided with additional openings, preferably radial, allowing the injection of gas to be used as reagents for different places in the lining. The injection of reactive gases both in the porous medium constituted by the packing, that near the electrodes, is performed radially or tangentially. This is illustrated in Figure 5.
The evacuation of the gases produced in the reactor is carried out radially or tangential way. Figure 5 shows an input (1) and an output (2) radial, as well as an outlet (3) and a tangential inlet (4), with respect to a bed or porous medium defined by the packing (5).

In fact, several other arrangements can be considered.
Many Reactor forms may be considered. For example, we can consider of the reactors in parallelepiped shape or even in spherical form. Different electrode arrangements can also be considered. Figure 6 presents a typical arrangement of electrodes interconnected in parallel.
This figure shows openings (1) that can be used for the injection of reagents or the evacuation of gases produced, the packing (2), the electrodes (3), the everything to inside a volume defined by the insulating material (4) (refractory and insulating thermal). As shown in Figure 6, the electrodes are connected in parallel and are electrically connected to a power supply (5). The made to use several electrodes allows to control locally the reactor heating levels (power density generated) and the flow 5 electronics.

Figure 7 shows an arrangement characterized by connected electrodes in three-phase mode. These electrodes are in the form of plates inside a cylinder (the figure shows a view from above). It is thus possible to provide 10 three electrodes and operate with a three-phase alternating current. This figure shows also openings (1) which can be used for the injection of reagents or the evacuation of gases produced, the packing (2), the electrodes (3), the everything to inside a volume defined by the insulating material (4) (refractory and insulating thermal). As shown in Figure 7, the electrodes are connected to a 15 power supply (5).

It is even conceivable to induce an electric current inside the filling by adding an induction coil around the reactor or in the refractory wall and use a non-conductive wall for the reactor.
The arrangement presented in Figures 2 and 3 is preferred. Reagents gaseous are injected into a feed opening presented by a hollow tube (the), then pass into a second hollow metal tube (2a), which is part of a metal electrode itself consisting of the hollow tube (2a) and a disk hollow (4a). The electrode is electrically isolated from the tube feeding device (1a) by the use of a device (5a) made of a material insulating electric, allowing the passage of gases. The gaseous reactants go to through openings (6) of the hollow disc (4a) of the electrode and come into contact with the metal lining (7). The latter constitutes a porous medium presenting sufficient atoms of the catalyst metal in contact with the gaseous reactants, and whose volume of interstices or pores allows a residence time of reagents large enough to promote the efficiency of the reaction of reforming.

The gases resulting from the reaction are evacuated by passing through openings (6) on the hollow disk (4b) of a second electrode or against electrode then are evacuated in the hollow tube (2b) of this same electrode. Subsequently, the gases products are evacuated in a second tube (1b) which is electrically insulated relative to the tube (2b) by the use of a device (5b) made of a material electrically insulating.
The electrically conductive and heat packing (7) taking place between the two disks defines a cylindrical reaction chamber. This chamber is contained in an enclosure (8) whose inner wall is covered a refractory material (9) and a thermal insulation material (10). The refractory material has a shape such that it delimits the volume of the bedroom of reaction, which is defined by the diameter of the disks and the volume of the packing. The diameter of the packing volume is preferably equal to that of each of the discs of the electrodes.

The reactor may be provided with different openings (3) allowing injecting, preferentially radially, gaseous reactants within the middle porous filling, in order to optimize the reaction that is wants to achieve in the reactor.

The outer wall made of steel is grounded (16). This wall is advantageously electrically isolated with respect to at least one of the two electrodes, by the use of insulation seals made of dielectric (11) (eg Teflon, Bakelite, etc.).

The two electrodes are connected by anchor points (12a) and (12b) to a power source (13) of the DC (direct current) or AC type (alternating current). Power supply serves as a source of energy Requirements for carrying out this reaction. The amount of energy will be adjusted to maintain the temperature level in the reactor. The level of temperature is measured using one or more thermocouples (14).

Figure 4 shows an alternative arrangement. Following this arrangement, gaseous reactants are injected into openings (only one is shown by the supply) (la) through the reactor wall in order to to preferentially inject gas radially in the vicinity of the electrode to the entrance (4a). Gaseous reactants come into contact with the lining catalytic conductor of electricity and heat (7). The latter constitutes a porous medium having sufficient atoms of the catalyst metal in contact with the gaseous reactants and whose volume of the interstices allows a time of reagents remain sufficiently large for the yield of the reaction of reforming.

The gases resulting from the reaction are evacuated by passage through openings (1b) located on the periphery of the reactor (only one opening is shown by.
the figure). These openings are such that the evacuated gases circulate preferably radially with respect to the second electrode (4b) before to be evacuated. Each of the two electrodes consists of a solid disk, respectively (4a) and (4b), extending through a feed rod of current, respectively (2a) and (2b). Each of the discs of the electrodes is in contact with a shoulder (5) of cylindrical shape made of material refractory.

The reactor may be provided with various openings (3) for injecting of the gaseous reactants preferentially radially inside the medium porous what constitutes the packing. This in order to optimize the reaction that one longed for perform in the reactor.

The lining (7) takes place between the two electrodes and defines a chamber of cylindrical reaction. This room is contained in an enclosure (8) containing a refractory material (9) and a thermal insulation material (10). The refractory has a shape such that it delimits the volume of the bedroom of reaction, which is defined by the diameter of the disks and the volume in bulk of packing. The diameter of the packing volume is preferably equal to that of each of the discs of the electrodes.

In all cases, the electrodes are made of metal, preferably of steel ordinary.
The two electrodes can be identical or designed in different ways.
However, they allow a flow and a dispersion of the gases to interior of the reaction volume defined by the porous medium constituted by the packing contained between the adjacent faces of each of the two discs of the electrodes.
Preferably, these electrodes are identical in order to simplify the construction such a device. In addition, to facilitate electrical contact between the electrode and the lining, each electrode is provided with protuberances and or protrusions (15) allowing a certain gripping.
The packing is preferably in filamentary form as are the commercial steel wool. This packing contains powder or balls Made of metal or metal oxides, ceramic beads with metal coating, or a mixture of these elements. It contains advantageously metal elements of different shapes. The metal is preferably based on iron but can be formed of any metal of transition of group VIII or a mixture thereof.

The operating temperature is generally between 600 and 1,500 C.
The operating pressure is between 0.5 and 10 atmospheres. Preferably, the apparatus operates in the vicinity of atmospheric pressure. Gas fed into the reactor are mixtures containing biogas, carbon dioxide, hydrogen, methane, water vapor, light hydrocarbons such as those found in natural gas and / or organic compounds based on carbon atoms, hydrogen, nitrogen and oxygen.

The gas mixture contains nitrogen, argon and even a little air. The However, the amount of oxygen in the gases is small enough not promote the formation of carbon formation precursors (molecules unsaturated such as acetylene, aromatic compounds, etc.). The amount oxygen is preferably less than 5% by volume in the diet of the gas. If there is oxygen in the reactor, the addition of water vapor helps to prevent or limit carbon formation.

The gaseous mixture is previously desulphurized to prevent poisoning catalytic packing because sulfur is easily absorbed by the iron of the lining. However, the desulfurization of reagents in a reactor zone containing sacrificial packing and replace the trim as needed in this area or regenerate the iron through a process oxidation of pyrite according to the following reaction:

FeS + 1.5 02 -> FeO + S02 (9) Replacing the lining can be done inexpensively especially when the one-it is made of iron or commercial steels.

The electrical source consists of a current transformer in the case alternating current (AC) power supply or a rectifier current in the case of a DC type power supply (DC). The power of the power source is calculated according to the needs energetic reactions of the reforming reactions concerned, which are laws of thermodynamics. The minimum current intensity that the electric source is calculated by the following equation:

Iminimum =% = F (10) in which: Iminimum is the minimum current to be applied, expressed in AT;

1 is a parameter that depends on the geometry of the reactor, the type of packing, the conditions of operation and the gas to be reformed, which is empirically determined by the experimental method Described in the description; and F is the molar flow rate of the gas to be reformed, expressed as mole of gas to be reformed / second.

Typically the value of 1 is greater than 15 C / mole.
EXAMPLES
The following examples are presented for illustrative purposes only would know under no circumstances be interpreted as constituting any limitation of the present invention. These examples are given to better illustrate the present invention.

Example 1 Laboratory reactor fed with a mixture of methane (CH4) and carbon dioxide (CO2) saturated with water vapor (H2O) A small capacity compact electric reactor is described in a manner 2 and 3. According to the assembly of such a reactor, the gaseous reactants, in this case methane (CH4), carbon dioxide (C02) and water vapor (H20) are injected into a feed opening consists of a hollow tube (la) and then pass into a second hollow tube in metal (2a) which is part of a metallic electrode itself of hollow tube (2a) and a hollow disc (4a). The hollow tubes (la) and (2a) as well than the hollow disc (4a) are made of mild steel (carbon steel).
The electrode inlet (2a and 4a) is electrically insulated from the tube power (la) by the use of a device (5a) made of Teflon, an insulating material electrically, allowing the passage of gases. The gaseous reactants go to openings (6) of the hollow disc (4a) of the electrode and enter into contact with the metallic lining (7), which consists of wool of steel BullDog type manufactured by Thamesvillê Metal Products Ltds (Thamesville, Ontario, Canada). The chemical characteristics of steel wool, determined by chemical analysis and expressed as a percentage by mass, are the following :
= Iron (Fe): 98.5% minimum = Carbon (C): 0.24%

= Manganese (Mn): 0.93%
= Sulfur (S): 0.007%
= Phosphorus (P): 0.045%
= Silicon (Si): 0.11%
= Copper (Cu): 0.11%
= Nickel (Ni): 0.03%
= Chromium (Cr): 0.03%

The reactor operates in the vicinity of atmospheric pressure; he is in made open to the atmosphere by its exit of gases. The gases resulting from the reaction (the gas synthesis) are discharged from the reactor through openings (6) sure the hollow disk (4b) of a second electrode (also called electrode) and then are directed into the hollow tube (2b) of this same electrode.
By subsequently, the gases produced are discharged into a second hollow tube (1b) dimensions, which is electrically isolated from the hollow tube (2b) by the use of a device (5b) made of Teflon, an electrically insulating.
The steel wool packing (7), electrically conductive and heat, taking place between the two disks, defines a reaction chamber of cylindrical shape whose dimensions are detailed below. This room is contained in an enclosure (8) made of stainless steel whose wall interior is covered with alumina (9), a refractory material, as well as of asbestos wool (10), a thermal insulation material. The dimensions relating to the reaction chamber are as follows:

= Enclosure (8) of stainless steel:
o 16.5 cm (6.5 inches) outside diameter;
o Length of 24.77 cm (9.75 inches);

Alumina cylinder (9):
o Outside diameter of 10.16 cm (4 inches);
o Inside diameter of 6.35 cm (2.5 inches);
o Length of 10.16 cm (4 inches).

The refractory cylinder of alumina has dimensions such that they limit the volume of the reaction chamber, which is defined by the diameter hollow discs (4a) and (4b) as well as the volume of the metallic packing (7).
The diameter of the volume of the lining is equal to that of each of the disks electrode, or 6.35 cm (2.5 inches). The metallic lining (7) is consisting of an alternation of compacted layers of approximately 1 cm each of BullDog steel wool with fine filaments and steel wool BullDog with medium filaments, so that the flow of gas passes through each of the layers in the direction of the thickness. The alternation of layers advantageously increases the resistivity of the lining. In total, 50 boy Wut of steel wool constitutes the packing, ie 25 g of the fine filament type and 25 g of the middle filament type. The outer wall is made of stainless steel (8) and is grounded (16) (ground). This wall is electrically isolated by relative to each of the two electrodes by the use of isolation gaskets made from Teflon (11).

Both electrodes, made of mild steel (carbon steel), are connected by anchor points (12a) and (12b) to a power source DC-type electric power supply (13), the latter being a rectifier of Rapid brand current with a maximum output power corresponding to 300 amperes and 12 volts. The gas inlet electrode is connected to the terminal positive (cathode) current rectifier, while the output electrode of gas is connected to the negative (anode) terminal. One of the two electrodes is mobile in the axis of the length of the reactor, that is to say that it can be moved during operation to maintain contact electrical connection between the lining and the electrodes as and when that the metal trim could see its geometry changed.

The dimensions and characteristics relating to the input electrode are the following:

= Hollow tube (la) :
o 2.54 cm (1 inch) length;
o Nominal diameter of 1.27. cm (0.5 inches);
= Hollow tube (2a):
o Length of 30.48 cm (12 inches);
o Nominal diameter of 1.27 cm (0.5 inches);
= Hollow disk (4a):
o Total thickness of approximately 1.27 cm (0.5 inch) corresponding to the thickness of two 0.65 cm (0.25 inch) disks each, which are welded together as shown in Figure 9, the first disc having a central hole of 1.27 cm (0.5 inches) for the hollow tube (2a) and the second, adjacent to the metal packing, including the projections (15) and the openings (6);
o 6.35 cm (2.5 inches) diameter;
O projections (15) of 0.635 cm (0.25 in), 13 in number and distributed as shown in Figure 9;
o Openings (6) of three different diameters, to the total number of 32, or 8 large 5.95 mm (15/64 inch), 16 means of 3-, 18 mm (1/8 inch) and 8 small of 2.38 mm (3/32 inch), distributed as shown in Figure 9, with the openings of larger dimensions in the radial direction.
The dimensions and characteristics relating to the output electrode are the following:

:
= Hollow tube (1b) o 2.54 cm (1 inch) length;
o Nominal diameter of 1.27 cm (0.5 inches);
= Hollow tube (2b):
o Length of 30.48 cm (12 inches);
o Nominal diameter of 1.27 cm (0.5 inches);
= Hollow disk (4b):
o Total thickness of approximately 1.27 cm (0.5 inch) corresponding to the thickness of two 0.65 cm (0.25 inch) disks each, which are welded together as shown in Figure 9, the first disc having a central hole of 1.27 cm (0.5 inch) for the hollow tube (2b) and the second, adjacent to the metal packing, including the projections (15) and the openings (6);
o 6.35 cm (2.5 inches) diameter;
O projections (15) of 0.635 cm (0.25 in), 20 in number and distributed as shown in Figure 9;
o Openings (6) of two different diameters, to the total number of 24, or 8 large 5.95 mm (15/64 inch) and 16 means of 3.18 mm (1/8 inch), distributed as shown in Figure 9, with the openings of larger dimensions in the direction radial.

The homogeneous distribution of the gases in the reaction chamber is ensured by the On the one hand, the electrodes have larger openings 25- dimension in the radial direction, and secondly, that the output electrode born has no opening towards the center, whereas it is the case for electrode input (see Figure 9).

The operating temperature is between 700 and 800 C; this one is mainly obtained by the passage of electric current. Temperature is measured with three K-type thermocouples (14) (1/16 inch) each being covered with a thin sheath (1/8 inch) ceramic. A first is introduced into the reactor, through the cylinder of alumina (9), so that than its end is as close as possible to the catalytic packing but without to touch. The other two thermocouples are introduced into the electrodes inlet and outlet, near the openings (6). Figure 8 shows a 5 diagram of the general arrangement of the laboratory reactor.

The above description relates specifically to the reactor. This one is from all obviously accompanied by ancillary devices thus forming a test bench full. Figure 10 presents a general description of the test bench.
10 This includes the following components:

= The laboratory reactor as described above;
= The current rectifier as described supra;

= A steam generator (optional use);

= A saturator (bubbler) of water vapor (optional use);
15 = a gas meter (Wet Test Meter);

= Flow meters for the flow measurements of each of the gases possibly be fed: methane (CH4), carbon dioxide (CO2) and nitrogen (N2);

= Compressed gas bottles as supplied by the 20 Boc-Gaz company: methane (CH4), carbon dioxide (C02) and Nitrogen (N2), all of 99% purity;

= Pressure gauges for each of the gas circuits;

= The instrumentation allowing in particular the reading of the temperatures measured by thermocouples.

In this example, the bubbler is used to saturate with water vapor the mixture of reactive gases (CH4 and CO2). The steam generator is not used for this example. The injection of water into the reactor is therefore possible by saturation of gaseous mixture by contact with hot water. Thus, reactive gases are pre-fed into the saturator, which contains of hot water. The saturator is actually a stainless steel vessel inside which the reactive gases are brought into contact with water, at a given temperature. The temperature of the saturated mixture is measured directly when he leaves the ship. This temperature corresponds to the dew point of the mixed ; it makes it possible to quantify the molar fraction of the water in the mixed gas intended to be injected into the reactor. The dew point is typically between 80 and 85 C. Table 2 shows the variation in calculated composition of the mixture injected into the reactor according to the point of dew saturated mixture.

Table 2 Variation of the proportion of water vapor depending of the temperature in a saturated mixture containing 1/3 mole of carbon dioxide (C02) per mole of methane (CH4) Saturation temperature Proportion of water vapor (Dew point) (Volume fraction) ( VS) 80 0.47 81 0.49 82 0.51 83 0.53 The operation of the reactor is carried out according to the procedure described below. For start a test, the reactor is first preheated gradually increasing the current in increments of 10 A at intervals of 5 minutes with nitrogen injection (N2) at a flow rate of 1.0 L / min. When the temperature reaches 300 to 400 C, a small jet of air is projected on the tips in Teflon reactor so as to locally cool these two tips. Over there then, the injection of the reactive gases starts, these being saturated with steam water where appropriate. Carbon dioxide (CO2) is always injected before methane (CH4), in order to prevent the formation of soot within the reactor.
The flow rates of the gases are adjusted according to determined setpoint values beforehand. Once the flow rates of the reactive gases are reached, the injection nitrogen is stopped and the electric current is adjusted to obtain in the reactor, the chosen temperature. For the purposes of the operation, the temperature of work is that measured at the gas outlet electrode. For stopping the test, the Nitrogen flow is reopened at 1.0 L / min, then the methane feed is (CH4), then we close that of carbon dioxide (C02) and finally, we close the current rectifier. The reactor is allowed to cool with the nitrogen flow (N2) up to an internal temperature of 300 to 400 C. At this temperature, we close finally feeding the nitrogen.

The input and output gases are analyzed using a chromatograph gas phase micro-GC type, a CP2003 model of the company Varian. This chromatograph is equipped with three columns for which the stationary phase and the carrier gas vary according to the gases to be analyzed. The detector is of type with thermal conductivity. Certified mixtures of gases from from the company Boc-Gaz are used for the calibration of the chromatograph.
The gases to be analyzed are collected in Tedlar bags (Polyfluoride vinylidene). The sampling procedure is described below. The bag is.
first rinsed 3 times with nitrogen (N2), then 3 times with the gas to be analyzed.
Then, the bag is filled to about 80% of its capacity with the gas to analyze :
this constitutes the sample. For the withdrawal of the gases produced, the bag is connected to the reactor outlet to minimize air infiltration at interior of the bag. Waiting time before the analysis is then required for the sample is at room temperature.

This example describes the operation of the laboratory reactor in of the specific conditions described below (reforming test No. 61102). The flow rates of the gaseous reactants are adjusted to the following values: 0.08 sL / min for carbon dioxide (CO2) and 0.25 sL / min for methane (CH4) designating standard, ie 20 C and 1 atmosphere). These gaseous reactants are at previously saturated with water vapor by bubbling into the saturator. The saturation temperature of the gaseous mixture injected into the reactor is C. The volume fraction of water vapor of the gas fed into the reactor is therefore 0.49 (see Table 2). After starting the test, performed according to the procedure described above, the West current adjusted so at reach a temperature of about 780 C (20 C) at the output electrode.
Table 3 reveals the main parameters measured at times corresponding to the taking of samples.

Table 3 Main parameters measured when taking samples of reforming test No. 61102 Sample Time Voltage Current Resistance Power Temperature (n) (min) (V) (A) (Ohm) (W) (C) 1 15 3.11 141 0.0221 439 805 2 80 2.98 143 0.0208 426 795 3,195 2.80 148 0.0189 414 793 4,250,156 0.0175 426,771 5,290 2.62 156 0.0168 409 763 Table 4 reveals the composition of the gas mixture collected at the exit of the reactor, this composition being determined by the chemical analyzes performed by micro-GC on each sample taken.

Table 4 Results of chemical analyzes of the product gas mixture during reforming test No 61102 Sample Normalized volume concentration anhydrous base (11) (%) (%) (%) (%) (%) 1 67.86 29.80 0.59 0.41 1.35 2 70.53 26.35 1.29 0.96, 0.88 3 64.08 33.50 0.48 0.58 1.36 4 68.06 29.24 0.51 1.36 0.82 5 68.98 27.95 0.36 1.78 0.92 The results presented in Table 4 are consistent within the mistake experimental, with values based on equilibrium calculations.
thermodynamics for the same temperature level.

Example 2 Laboratory reactor fed with a mixture of methane (CH4) and carbon dioxide (CO2) saturated with water vapor (H2O) This second example describes the operation of the following laboratory reactor operating conditions similar to those indicated in Example 1 (test of reforming No. 71102). For this example, the operating period `is 340 minutes.

Table 5 reveals the main parameters measured at times corresponding to the taking of samples.

Table 5 Main parameters measured when taking samples of reforming test No. 71102 Sample Time Voltage Current Resistance Power Temperature (n) (min) (V) (A) (Ohm) (W) (C) 1 85 2.75 155 0.0177 426 793 2,160 2.54 160 0.0159 406 775 3 220 2.44 160 0.0153 390 764 4,280 168 0.0147 415 763 5,340 2.47 175 0.0141 432 762 The results presented in Table 6 are easily matched within the experimental error, with values based on equilibrium calculations thermodynamics for the same temperature level.

10 Table 6 Results of chemical analyzes of the product gas mixture in reforming test No 71102 Sample Normalized volume concentration anhydrous base (not ) (%) (%) (%) (%) (%) 1 58.07 33.54 0.47 0.80 7.12 2 61.09 35.44 0.25 1.86 1.37 3 61.50 32.83 0.37 4.63 0.67 4 64.32 30.95 0.27 3.91 0.54 5 64.37 31.22 0.32 3.44 0.64 In summary, the present invention is based on a judicious use of electricity characterized in particular by the following:
= not resort to current transforming processes on power electronics;
= to use an electronic flow by passage of current for support catalysis phenomena; and = potentially favoring the establishment of electric micro-arcs dispersed to further catalyze the reforming reaction.

The use of ohmic heating of a direct conduction lining its proved to be a simple way to introduce electricity as a source of heat for performing endothermic reactions. electricity can be direct current or AC or even three-phase. In the where alternating current would be used at the network frequency, the current transformation simply boils down to a potential adjustment by the use of simple transformers.

It has therefore been possible to electrically heat a lining consisting of metals known to catalyze reforming reactions of natural gas to the water vapour. The packing used thus proved to constitute both a heating medium and a catalyst for carrying out the reaction. This metal has been effectively used in the form of powder, a bed of granules, balls, rods, platelets or in a form of Filamentous structure as long as the contact area was sufficient for heat the gases and catalyze the transformation process.

Although the present invention has been described using implementations specific, it is understood that several variations and modifications may himself graft to said implementations, and the present invention aims to cover such modifications, uses or adaptations of the present invention according to general, the principles of the invention and including any variation of the present description which will become known or conventional in the field of activity in which himself found the present invention, and which can be applied to the elements essential mentioned above, in accordance with the scope of the following claims.

Claims (38)

1. Electric reactor for reforming, in the presence of an oxidizing gas, of a gas comprising at least one hydrocarbon, optionally substituted, and/or to at least one organic compound, optionally substituted, comprising atoms of carbon and hydrogen as well as at least one heteroatom; said reactor including:

- a speaker;

- a reaction chamber equipped with at least two electrodes and located inside the enclosure, said reaction chamber comprising at least one porous and conductive packing material which forms in whole or in part a reforming catalyst, said packing being electrically isolated from the wall metal of the enclosure so as to avoid any short circuit;

- at least one gas supply to be reformed;

- at least one oxidizing gas supply, separate or not from the supply into gas to be reformed;

- minus one outlet for the gases resulting from the reforming; and said electrodes being able to be energized using a source of running to generate electron flow in the conductive packing between the electrodes. 2. Reactor according to claim 1, in which the packing material conductor is chosen from the group consisting of the elements of group VIII
of the periodic table and alloys containing at least one of said elements. 3. Reactor according to claim 2, in which the packing material consists of at least 80% of one or more group VIII elements selected from iron, nickel and cobalt, and alloys containing at minus 80%
one or more of these elements. 4. Reactor according to claim 3, in which the packing material is a carbon steel. 5. Reactor according to claim 1, in which the packing consists elements of the conductive material in the form of straw, fibers, filings, of sintered, balls, nails, threads, filaments, wool, rods, bolts, nuts, washers, chips, powders, granules or plates perforated. 6. Reactor according to claim 1, in which the conductive packing forms a porous medium with a surface area of more than 400 m2 of exposed surface per m3 of the reaction chamber. 7. Reactor according to claim 1, in which the material has at the dense state an electrical resistivity at 20 C between 50 x 10-9 and 2,000 x 10-9 ohm-m. 8. Reactor according to claim 1, in which the conductive packing has a porosity index between 0.50 and 0.98. 9. Reactor according to claim 1, in which at least one of the electrodes is a hollow electrode, the hollow electrode is the inlet port gas to reformer or a conduit for supplying the gas to be reformed and the oxidizing gas. 10. Reactor according to claim 1, in which at least one of the electrodes is a hollow electrode, the hollow electrode is the gas outlet resulting reforming. 11. Reactor according to claim 1, in which at least one electrode is of the perforated type and it comprises openings which have a diameter of more 25 µm, the openings being distributed uniformly according to a density of at more 100,000 openings per cm2 of electrode surface. 12. Reactor according to claim 1, comprising at least two electrodes metal, each consisting of a tube and a perforated hollow disc, the disc being located at the end of the tube opening into the chamber of reaction and in contact with the reaction chamber lining. 13. Reactor according to claim 1, in which at least one of the electrodes has a face exposed to the packing which is provided with protrusions and or protrusions that are conical or needle-shaped. 14. Reactor according to claim 1, in which the reaction chamber contains, in addition to the conductive filling, non-conductive materials and or semi-conductors and/or electrically insulating, arranged in the chamber of reaction so as to adjust the overall electrical resistance of the packing. 15. Reactor according to claim 14, in which the materials not conductors and/or semiconductors and/or electrical insulators are ceramics or alumina. 16. Process for the reforming of a gas comprising at least one optionally substituted hydrocarbon, and/or at least one organic compound optionally substituted which comprises carbon, hydrogen and au least one heteroatom, consisting in bringing the gas to be reformed into contact with a gas oxidant in a reaction chamber, characterized in that:
- the reaction chamber contains a conductive packing material electricity forming in whole or in part a reforming catalyst, the material being placed between electrodes;

- the electrodes are energized to produce an electric current direct or alternating generating an electronic flux in the packing. 17. Method according to claim 16, characterized in that it is implemented work in a reactor according to any one of claims 1 to 15. 18. Method according to any one of claims 16 or 17, in which the reaction chamber lining is preheated prior to feeding in gas to be reformed and into oxidizing gas, at a temperature between 300°C
and 1500°C, under an inert atmosphere. 19. A method according to claim 16, wherein the oxidizing gas is consisting of at least one gas selected from the group consisting of carbon dioxide carbon, carbon monoxide, water vapor, oxygen, oxides nitrogen and mixtures of at least two of these components. 20. Process according to claim 19, in which the nitrogen oxides are NO, N2O, N2O5, NO2, NO3 or N2O3. 21. Process according to claim 16, in which the gas to be reformed contains additionally one or more gases selected from hydrogen, nitrogen, oxygen, water vapour, carbon monoxide, carbon dioxide, and gases inerts of group VIIIA of the periodic table, or mixtures of at less two of these. 22. Process according to claim 16, in which the gas mixture introduced into the reaction chamber contains less than 5% by volume of oxygen. 23. A method according to claim 16, wherein mixing the gas with reformer and oxidant gas consists of 25-60% methane, 0-75%
of water vapor and 0 to 75% carbon dioxide. 24. A method according to claim 23, wherein mixing the gas with reform and oxidizing gas consists of 30-60% methane, 15-60%
of water vapor and 10 to 60% carbon dioxide 25. Process according to claim 16, characterized in that it is implemented works at a temperature between 300 and 1,500°C. 26. Method according to claim 16, characterized in that it is implemented operates under a pressure in the reaction chamber which is greater than 0.001 atmosphere. 27. Process according to claim 16, in which the residence time of the reagents is greater than 0.1 seconds. 28. Implementation of the method as defined in claim 16, for the reforming of a gas consisting of at least one C1-12 hydrocarbon, optionally substituted by groups: alcohol, carboxylic acid, ketone, epoxy, ether, peroxide, amino, nitro, cyanide, diazo, azide, oxime, or halides, which hydrocarbons are branched, unbranched, linear, cyclic, saturated, unsaturated, aliphatic, benzene or aromatic, and having a boiling point below 200°C. 29. Use according to claim 28, characterized in that the halides are fluoro, bromo, chloro or iodo. 30. Implementation of the method as defined in claim 16, for the reforming of natural gas. 31. Implementation of the method as defined in claim 16, for the reforming of a biogas consisting of 35 to 70% methane, 35 to 60% gas carbon dioxide, 0 to 3% hydrogen, 0 to 1% oxygen, 0 to 3% nitrogen, from 0 5% hydrogen sulfide and/or ammonia and steam. 32. Implementation of the method as defined in claim 16, for the reforming of a natural gas consisting of 70 to 99% methane, from 0 to 10%
ethylene, 0-25% ethane, 0-10% propane, 0-8%
butane 0 to 5% hydrogen, 0 to 2% carbon monoxide, 0 to 2% oxygen, 0-15% Nitrogen, 0-10% Carbon Dioxide, 0-2% Steam water, 0 to 3% of one or more C5-12 hydrocarbons and traces other gases. 33. Implementation of the method as defined in claim 16, for the reforming of a gas consisting of at least one organic compound having atoms carbon, hydrogen, and one or more heteroatoms chosen from oxygen and nitrogen, comprising one or more functional groups chosen from the band consisting of alcohols, ethers, ether-oxides, phenols, aldehydes, ketones, acids, amines, amides, nitriles, esters, oxides and oximes, and having a boiling point below 200°C. 34. Process according to claim 16, in which the reforming reaction is catalyzed by micro-arcs jumping between the packing particles or by sites activated on the surface of the packing particles by the accumulation of loads and/or by the passage of electric current. 35. Use of one or more electric reactors as defined in claim 1 for:(i) the production of syngas for use in the manufacturing of methanol for installations with an electrical consumption of 1 at MW; (ii) recovery of biogas into energy and/or chemicals generated through sanitary landfills; (iii) the production of hydrogen for of the fuel applications related to road transportation; and (iv) the production hydrogen for portable or stationary applications. 36. Use according to claim 35, characterized in that the fuel applications related to road transportation are power of the cars and buses. 37. Use according to claim 35, characterized in that the portable or stationary applications are battery power combustible intended for residences and road vehicles. 38. Use of the method as defined in claim 16 for the desulfurization of gases containing sulfur.