DE1671679A1 - Fuel cell and method for operating this fuel cell - Google Patents

Description

RICHPIEH) COMPANY

Fuel cell and process for the operation of this »fuel cell.

The invention of bnti-ifffc öins fuel cell »in the an On the spot Wanserafcoff erxougt vjlrd, and sia besweokt a process and aino Vorrlohtung that the size of the Increase in pressure drop across the circulation catalyst reduces the amount of fuel cell lirafonriiingazone in tier is included, "o that a fuel cell is created, the Ubar «works reliably for a long period of time.

With pulp waves never aie in the US. Oovernment Report Nb. AD 613031 , referring to a development

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from fuel sources with liquid hydrocarbons, KiM a hybrid of a carbon-containing fuel and Dawtif introduced into a UiuwAndlungäxutte, which is arranged in the Bromiafkoffnslle, and hydrogen from ÖJfseugöü, the sodatji) in the electrolyte by suitable © executions for an electrochemical reaction in the ropes is directed generally "oinan Nlukolkatnlysator, dei" his katalyxißcbea Vfix ^ c "aEskelt and its low" cost includes the ifciforcRirsgskatalyaafcor, DER inrierhßlb the Itofonfmingszon "to ^ oordnot eats, contained in the steam dor carbon" is initiated related will. E3 However I'c βteilt that at Brerinatofrzellen io Bferftioh of about 25o C the ^e bit DaTiokiitofall about 55o ° C, the steam "Brennstoff2" .führung Uher the Hiokel "fcaftt, lyßator _# eats the asOne included in the & Uhswandiun, practicing ¹ i Z * XtJ? ii \ ime doB ZiflXenbotriebe hinwag increased, this

Pressure drop * is particularly pronounced when Feeding av «r stops" ni "from steam to carbon-containing ones Fuel below 5 NoI steam per KoI carbon in dew Fuel lies. The vyrveidnag of carbon containing Brennefcofi'en * the at least two carbon atoms per Contain rubbish (e.g. carbon dioxide over methane), result in an even greater increase in pressure & b'all over ßetrlebßzaiten of customs. If ".B" a n ^ mpfin a UtowandlunfiiJEana ia ratio of

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Introduced 5 moles of water per haul carbon \ i ± vu _t erhöhteich so the pressure drop across a conventional liickelkatalyaator as © r. the transition zone is contained, gradually increasing to uirvsn vert from about oinor atmosphere to approximately i «? Conversion or operating hours at around 500 ° C.

Since in your previous case the Uta conversion is approximately

one atmosphere! takes place, then training A

of the pressure drop In this size a further generation of Hydrogen in the UFO conversion zone. If the steam / carbon fiber ratio reduced viird, then festgentel.lt, dail the union of the t »ruo! cabfalla is accelerated. So achieved ", if oi; i steam / carbon ratio voti J5.3 mol Darapf pyvi Hol carbon related vfli ^ d, the pressure drop oine Atrr.oEphär "after 9 hours of operating time" for one Darupf au KJoiaen ^ to ff ratio of about 2, the Pressure drop of one atmosphere after approximately 4 hours of operation

ä trlf »>« 5i: eit. If so, the molecular weight of the hydrocarbons

material is increased * so that the pressure drop is achieved elcon value; from an atnoaphire to a considerably lesser one Tent, and lit dim case that octane as fuel and egg: i Dauopf EU KoiUenstoffzufUhrungverliSltniR of S, 5 vervmncit i «lrd, hears the Eraugunf; from Waesersloff to ungen:!: '* j!> Stunrton <Ier JOfispf conversion at around 5 °°° C for a on.

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1 G 3 8 3 3/1 3 2 5

Obviously, however, it is for many fuel cell applications required that the fuel cell be continuous and reliable over times longer than 8 or Io hours works away and it is often necessary that the Fuel cells continuously for many thousands of hours Are operational. As a result, the formation of a pressure drop can cause the fuel cell to run after a short operating time fails, will not be tolerated; This problem has led to the use of catalysts other than Nickel, which, "although often less effective and more expensive, operation of the fuel cell for longer periods of time ~ allow away before a significant pressure drop develops in the Uta conversion zone.

According to the present invention, a method for operating a fuel cell is specified, in which a mixture of etine hydrocarbons of at least two carbon atoms and steam in a ratio of steam per mole of carbon in the hydrocarbon of 2 to 5 is introduced into a conversion zone which has a catalyst contains, which utsfasst a nickel-coated refractory substance or refractory bricks that contain from 0.5 to 2o % of an alkali or alkaline earth

j. -hydroxyds or carbonate contains the weight fraction of, or a nickel-coated alkaline earth oxide, at dsm a reaction in the range from 25o ^e C to 55o ^e C takes place under a pressure of less than 10 atmospheres, and

in which the hydrogen formed passes through a permeable membrane v _v 109883/1325

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passed into an electrolyte for electrochemical reaction will.

At the same time, a fuel cell is specified which contains an electrolyte cell with an anode and a cathode which is separated from an insulation zone by a hydrogen-permeable membrane in the anode, in which a winding « _Λ

Umforraungskatalysator is arranged, the particles of a nickel · »^ coated refractory material» from about 0.5 % to about 20 % of an alkali or alkaline earth metal «oxide.3,« »hydroxyds or« carbonate, based on the weight of the Metal "or contains an alkaline earth oxide soaked in nickel *

In this way, continuous and reliable operation of a fuel cell under a particular set of conditions is obtained through the use of a particular type of nickel catalyst, which has been found to be critical of the successful practice of the invention. According to the invention, this can be achieved by the method for operating a fuel cell with an anode and a cathode "which are arranged in an electrolyte", the anode being equipped with a hydrogen-permeable metal membrane for the transfer of hydrogen through it into the electrolyte during operation of the cell is, and can be achieved with a conversion zone that contains an conversion catalyst adjacent to this membrane,

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167167S

In this process, a mixture of 2 ble about 5 koles per oil of carbon is introduced into one-m carbon-containing broil, which contains at least two carbon atoms per foil, we! * This mixture is poured over this conversion catalyst at a temperature of about 25o ° C to about 55o ° C under a pressure of less than about 10 atmospheres to generate hydrogen, this conversion catalyst having particles of at least 2 seconds oliarl des? Class that consists of (a) a nickel uberaoisenan .fire-resistant material, dag from about 0.5 % to about 20% of an alkali or SsHialkalimetalloxydar., "T" or carbonates based on the weight of the metal ^ and (b) a nickel-coated alkaline earth oxide, and in which this hydrogen is converted into this electrolyte for the electro-thermal reaction you raw this membrane,

'

^{w to} reduce the size of the increase in the pressure drop across the Uta * wanulungskatalyftator.

* I

In a further implementation, "for the invention, a new and original fuel cable is provided" which has a lead-acid cap and an anode and a cathode "which are so disordered that they can be found in an electrolyte when this fills this chamber aone adjacent to this © anode »the? for the supply; vo

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Hydrogen from steam and a carbon containing Fuel is provided, this anode being a hydrogen permeable metal membrane for the transfer of hydrogen, which has been produced in this zone, contains in this electrolytic Kanner and contains a conversion catalyst that in this stone arranged 1st and particles of at least contains some kind of classes that are made up of

a) a nod 3. related fire-resistant material which contains from about 0.5% to about 20% of an alkali or alkaline earth metal oxide, hydroxide oxide or carbonate, based on the weight of the metal and

b) a nickel-plated alkaline earth oxide, this catalyst being characterized by the ability to lower the rate of increase in the pressure drop across the ötawandlungsiono during prolonged operation of this cell when the steam in this zone contains a carbon-containing fuel containing at least two carbon atoms per Molecule contains, at temperatures below about 55 ° C, pressures below about 10 atmospheres, and steam to carbon stocks of below about 5 cole of steam per mole of carbon in this fuel

109883/1325 BAD

According to the invention, a mixture of from about 5 to about 5 moles of steam per mole of carbon in this carbon-containing fuel containing at least two carbon atoms per molecule is introduced into the application zone. In general, low steam should be used to generate carbon, so as not to lower the hydrogen gas pressure in the anode and thereby lower its oxygen dissipation potential and consequently the rope tension achieved Carbon ratios are introduced into the Uftwimdlimgssone, if an additional burden on the thermal efficiency of the fuel cell is necessary because of this) connection it has been found that a ratio of about 2.1 oil contains about 2.7 mol of steam per mol of carbon in the carbon Fuel should be used preferably.

The iktecnwindtgkelt; or the flow rate with which the fuel-Dwopf mixture is initiated in dia ütawandlungsxonc, can within wide limits and depends on the size the ütBMazii? JLutigS £ one in the cell "of the speed with which the stroie from the cell is balanced, 4-way swelling and the printout on which the conversion is performed. from From a practical point of view, however, the upper limit is

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"Ifio Iw21" £ "lfge given cell feel an arbitrarily given of Itotitfetosiradi & gungen) the amount of flow or oe

the steam "fuel introduction into the disorder" is the value at which the conversion of the fuel falls below 100% Hydrocarbons of lower ifc "l" fled. Sorait falls the conversion of the fuel uiitar lco % nenn unreacted fuel occurs at the output probe of the conversion S2one. To give an example of how an Olctane-Daiapfraiechung is introduced into the conversion "xona" so A 100% conversion would be achieved, and the waste gases would contain hydrogen, methane, chlejad oxide, carbonium oxide, and water, but are free of ootane, except perhaps in trace amounts.

The carbon-containing fuels that are called to carry out the? Invention are useful include XSohlemraseer * substances that contain more than 2 carbon atoms per molecule, like s «B. Xthane, propane, butane, penton, hexane, heptane, Ootan, etc .; and mixtures thereofj petroleum fractions; aliphite alcohol, including ethanol, propanol, öutanol, iißv «; // liquefied petroleum gases; and JP-Rreoistoffe «. . Other carbon-containing fuels that D-ai the average

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6 ** Load suitable and should be suitable for a compartment on the Bind Xlega «In general, allphatiache and naphthanic additives are preferred because of their high water content.

The function used in carrying out the invention "can be introduced into the conversion zone at any suitable temperature *, preferably at a temperature which corresponds to the temperature reached in the conversion zone of the cell during cell operation". Preferably, the steam mixed with the hydrocarbon-containing fuel to prepare a suitable mixture at some point prior to the introduction of the steam and fuel into the conversion of the cell.

ψ The terapereture at which the Ito conversion reaction is carried out in the fuel cell can range from about 25o * C to about 55o ^c . The cell has been found to be ineffective at temperatures below about 250 ° C. Corrosion problems occur at temperatures above approximately 55 ° C and the use of expensive contact materials is required, which makes fuel cell operation less attractive

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* that the optimum actual temperature is in the range of approximately kao ⁹ C to approximately 500 * C and in particular to approximately 45o ° C.

The pressure «under which the Um * ajidlungs reaction gen & 8 dem

Inventive procedures can be carried out, know until au uagiifJüar Io atmospheres range. About the operation of the cell

Print, however, uafcerfcalb from tmeafähr Io Atsxjeiphären, ™ omit all my cu d <tr extraction of hydrogen

Partialdruoken Uw BreonstoiTanode. Of course, from the perspective of a fully integrated operation, there is a change in the fan rate reaction in the case of atraospheric conditions, which avoids difficulties which can then arise "for whom the cell is operated under significantly higher levels of risk."

VIe above footgsstel It was "is used in the subject of the invention | Process Dumpf found, which converts a carbon-containing agent in the presence of a special type of nickel catalyst, etc., the use of which is critical to the successful implementation of the invention. The catalysts which can be used in accordance with the present invention contain particles from a '' it nickel plated feuerbe material * comprising from about 4 to about 7o wt.% u Ȁ o of about _# 5% to about 2O% of an alkali"

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or ErdallCRlimetaloxyds, -hydroxyds or -carbonate on da * weight of the fie tr. Xl contains β. Examples of suitable Fire-resistant materials are silica, kieselguhr, zircon earth, Alurolniuinoxyd, ftaturtone., Sillciur.oxyd-Aluminiuraoxyd,

Metal »artid # including carborundum, titanic oxide and Molecular sieves.

You alkali or alkaline earth metal oxides, hydroxides and "carbonates" those contained in the aforementioned catalysts include bind the oxides, hydroxides and carbonates of metals such as sodium, Kaiium, lithium, rubidium, cesium, calcium, strontium, Magnesium and barium. Examples of specific compositions that fall into this class are sodium oxide, Potassium hydroxide, lithium carbonate, calcium oxide, strontium hydroxide and magnecsium carbonate.

P In addition, when carrying out the invention

Usable catalyst be a nickel-coated alkaline earth oxide (? .B. Caloluntoxyd, Magneeiuxnoxyd, barium oxide), that has a nickel content of about 4 to about 70 ow. ^ owns.

One group of catalysts useful in the practice of the invention can be obtained by treating any. Commercially available porous refractory catalysts can be made from about Jf to ungofMhr Jo% nickel

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contains nlt «jUotem or more of the above-mentioned oxides, hydroxides or carbonates. With an allcal oxide, hydroxide, or carbonate , this can be achieved by immersing the catalyst in an aqueous solution of the additive and then drying the catalyst in a suitable oven. For example, a 25 S catalyst was made from 2o to 50 mesh Girdler G * 6o nickel on aluminum

in about 15 cc. immersed in a 4.16 a solution of sodium hydroxide ™ which was completely absorbed. Dar catalyst was then dried in an oven at l4o ^e C. It was found that the alkali content of the catalyst obtained was 5%, expressed as a total of £ 75.

Felt rfaseer-insolated earth calcium oxides, «hydroxytle or • Hydrogen carbonates for use in the manufacture of Catalysts used in the implementation of the present Invention are usable, are desired, so kaiin 'an i

Waeser-soluble alkaline metal composition can be used to make the fire-resistant materini extracted with Mick oil. 2u oil precursors, and the hydroxide or carbonate of the metal can be unifolently precipitated in place. For example, an aqueous solution of magnesium nitrate can be used to impregnate an O-60 Oirdler catalyst, and the impregnated catalyst can then be grounded with a gaseous stream of coil dioxide or with an additional aqueous solution of triumodium carbonate riagnos oarhonat to precipitate in the catalyst. If «iac QxyX £ o-

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If the catalyst is impregnated with magnesium, it can become unsafe in order to corrode the nitrate.

In addition, a fire-resistant nickel-plated catalyst is impregnated with a eats in the Wärrae ^ replaceable alkali or Erdalkaliraetallzusaissienaetzung, wio as a nitrate, acetate or W format, for example, can directly into the The fuel cell can be changed and the oxide and / or carbonate can be formed on site during the accident in the zone due to the conditions that exist during fuel cell operation, ie high temperature and the presence of CO ₂ .

Other processes for the preparation of alkali-aged nickel catalysts, which are used in the practice of the invention ^ yendable are "aind described in the Ü3 patent 3 Sol 214" in detn their use in the vapor conversion of naphtha Conditions is explained; which are different from and is opposed to the conditions to which the essential ones subject to the losing invention, what a readily apparent

A critical feature of the present invention is the use of a hydrogen-permeable membrane as a complete foenis of a wall of the Ustfox ^ nungszonci, dis den

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The above-mentioned catalyst contains * Such a membrane can contain any hydrogen-permeable Motalla membrane that is compatible with the environment, i. e. sufficiently resilient to the effects of the biting bfcw. It is a corrosive electrolyte, and which retains its physical nature in the teraperatuxes at which the transformation takes place. Examples of such membranes are palladium or hydrogen-permeable palladium alloys, such as a Silbex / Pailadlun alloy which contains 25% silver. 2u »better understanding of the fluid and a more detailed description of other nut silane r features * the present invention is intended in the following anh & nd "iner in d» v drawing shown Bel-

Embodiment ^ the erfindungsgea & jBen Yorviol ^ TUAG "liilutert trerdon in which the" iivzlge FIG t'.orociinitfe a ^ ihrfingsfoie shows by slno fuel cell arrangement, the VLR & Ausflihrjn ^ ffjro to the present invention.

As "must the drawing be seen, includes the fuel"

Io a fuel cell which has an outer li made of a non-conductive / impenetrable material and two electrodes, an anode 12 and a cathode 14, which are held in the housing by spacers 16 ₃ 18 and 2o, so that a conversion zone 22, the a treatment catalyst 24, which over the zone 22

109883/1328 _8A d

The catalyst 24 contains particles of either a nickel-coated refractory material which is from about 0.5 to about 20 $ 6 an ·· alkali or ErOalloaliaetftlloxyda, - Hydrojryde or carbonates, (such as, for example, an aluminum catalyst containing about 33% Nlokel and including sodium hydroxide in an amount of about 5.75 % expressed as sodium metal) or a nickel-coated alkaline earth oxide, such as nickel-coated magnesium oxide, the 23 % Contains nickel. The size of the catalyst particles varies depending on the width 22a of the conversion zone 22. Preferably, the particles should have a diameter that is "from one fifth to one tenth the width of the zone" «In order to introduce the fuel-vapor mixture and the oxidizing agent into the conversion zone 22 and the oxidizing agent space 28, respectively. The outlet lines 3% and 36 are provided for venting the ease. The cover is provided with a suitable passage opening 37 in order to draw off the water which is formed during cell operation from the electrolyte which is contained in the space 26,

During cell operation, the electrolyte compartment 26 is filled with a suitable electrolyte, such as a molten one

1Q9883 / 1325 _Bjm

S * ⁰ ORIGINAL

, 2..Q. one fünehimg out

filled u?: - d a BremistoffsufUhXaaig ^ »Mo a heating from a carbon containing B UiMi ßaicpf comprises, is introduced into the Umwarialim'-issiQne 22 line jjo. The ratio of steam to carbon-containing BJ ^ erinstoff and the l? LuSnieiH £ © _e with; Before the line 30 is fed, valves 38 and 38 can be adjusted appropriately, with which the control of the steam or the carbon dioxide can be recognized * In zone 22, the steam reacts with the hydrocarbon above the catalyst PA , whereby stoffeas produces witvä. The anode 12 contains a substrate, such as, for example, microporous carbon, which is exposed on the front side, the de »eiektXOlyten * a non- ovots & stoff durohläaise MBtallaajabrane 42, about fms. Although the thickness of the membrane 42 may vary in one area, the "membranes" will have thicknesses of the order of magnitude of 00023 cm (o, o o oΐ inches) or less - but thicker casings are of course possible permeable Metsilliaembrane & n, ul® are self-supporting, 3u use and deis correspondingly ktam dio po Kohlanuritarleger or ^r iräg ^ r 12 away from 511.

Wessi 4lie Zello ^ jatairtot nardsn eol.i, oo uizd the 26 "with a suitable electrolyte". like sfcwa

, and füi »: -? &

in TFAR Oi ^ ^ flsiiö dismis of img. ^ fähi ^'s 433 CUiöi> .ii

BATH

A mixture of a carbon-containing fuel (such as propane gas) and steam is then introduced into the conduit 22 through the conduit jJo. The ratio of fuel to steam and the additional amount or speed at which the mixture is introduced is regulated by suitable actuation of the control valves 38 and 40. In the ^ entry into the home Utawandlungozone 22 and contact with the catalyst 24 of the fuel and the steam react, so that hydrogen gas is generated. When the current is withdrawn from the cell through lines 44 and 44 &, the hydrogen produced is caused to pass through membrane 42 and into the electrolyte

In which electrolyte space 26 an electrochemical reaction is carried out. For example, with a supply ratio of 6 * 9 Hol Dasapf per mole of propane (Daapf to carbon "7" rhgltnli3 ii, 3), 4 _S 4 ml (STI ¹ ) propane per hour were introduced into the conversion, which increased to 4% * C and approximately c ^ ner P'A & noephlire gtihaltesi fmrde * 4.8 Ampdre stroa were derived from 4 ropes at a tension of ο, Τβ 7ü'it. An analysis from bva tsoden O & bo ergßb * dsJ can contain propane in it »ciHelgt # dad the {SsMendl * * 'g of the fuel loo ^

ΐ?. «β Söllanböti'tebes winl tier / Jniökebfall ΛΡ over

■ 24 duiiih öina any geelf ^ iotö Biiirlichtung,

a QiitiOkuiJltuxmnnoiiieter · 46, geMtssaan, rlßßen einer ίϊβλ Hl «', who i ^' ffMii / r Jo connected Int * In ü« rd «» ^% »uä-i« Di ^ mpf

j O q ö S 3 / I 3 2 S

BATH ORIGINAL

Be "Hfi TOTR iftt & essiMtf efrtbJdtenu" Brawwtoff Gea ± "oht υβ & Airch dl" the mixture la the UMWA & dlunsezcn · reaches 22 * and desoen other Sehenkel old joined the outlet 34 "let gen by abg the exhaust gases from the tfciwandlungazone S2 **« « earth. As can be seen by a person skilled in the art, the ropes and the manometer 6 are drawn to scale.

Jla * ltra> Bratmstoffr.elle of the kind shown in the drawing, uurd © a mixture of steam and propane in the ratio vaa 2 _f 5 mol steam per mol carbon introduced. The Unrwand.lunse xoru "of the cell contained contained a Glrdler a-6o Ifciformungskatalyeator, the 2o ble 3o H" 3h granules "us plated with nickel Alumlniumicttfaeete" d s. ^ 3.1 $ 6 Kickül and 5.75% Hatriuahydroxyd, ale Katrittoraetall " Sine Otaforoung in the took place at a temperature of about 45o * C and one of about an Atooepbären «Was a kcottinulerlioher cell farm without any

beaexfebara Xn ^ erung la pruokabfall Above the catalyst bed £% n «« h «ixwr continuous operating time of more than looo 3ttind «n reached.

ΐ «The skids were old untreated and coated with Nolcel

a (Girdler) carried out the In arranged «rare», into which propane or Oetar «» n were introduced (steam to carbon ratio ie B *: * Ficb from 2 to 5), and a conversion was carried out at 45o ^e C and

r · AtmopphSre Druok performed α Even at ά $ η 10Γ883 / 1325

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- 2ο -

higher steam to carbon ratios (cLh. in the order of magnitude of 5) * found the increase in pressure drop across the Catalyst in the zone took place quickly and reached such a high value that the run was 10 hours after it started had to be ended. At lower steam too Carbon ratios (2 to j5) found an even faster one Increase the pressure drop across the zone, so that the run is aborted within 6 hours or less had to become.

The present invention thus provides devices with, therefore continuous and reliable operation of a fuel cell » where hydrogen is generated on site, over longer times can be achieved by increasing the rate of growth of the pressure drop across the conversion zone of the cell, which contains a nickel conversion catalyst is reduced. Because of the present invention are the possible applications for »oil fuel cells, which contain effective and inexpensive nickel catalysts, considerably has been extended

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Claims (1)

Claims ϊ · A method of operating a fuel cell, are in de leltet · Vapor and a KohlenwasserÄtoff in a UiBwanctlungszcme containing a Niokelkatalyeator "and in which the hydrogen generated by a permeable membrane into an electrolyte for an electrochemical reaction λ is conducted in this electrolyte, characterized in that the nickel catalyst comprises a plated with nickel refractory material from 0.5 $ to 2O% of a Alkall * Or Erdalkaliinetalloxyds, -hydroxyds or carbonate with respect to dos Nlckaigewieht, or a nickel Coated alkaline earth oxide contains noble the ratio of the steam per mole of KohJanatoff 2 to 5, whereby this hydrocarbon. wanlßstena swel contains carbon atoms and the steam and the hydrocarbon react at temperatures of 25o ° C to 55o ^C C under a pressure of less than 10 atmospheres S. ancestors according to claim 1, characterized in, üaQ daa ratio of steam au carbon containing fuel voii cheating 2.1 to 2.7 mole of D & ßjpf per haul carbon in the carbon-containing fuel " 3 »Method according to one of claims 1 or 2, characterized kamnaeiebnet that the Utow - ndlungoreaktlcn under pressure 10 9 8 8 3/1325 _BA0 of approximately one atmosphere. 4. The method according to any one of claims 1 to J, - characterized in that the Ifoiwandlungsreaktion at a temperature from about 4oo * C to about 5oo ° C. 5. The method according to any one of claims 1 to 4, characterized in that the feed unit or speed of the Mixing in the conversion zone is below the value in which the conversion of the carbon-containing fuel falls below 100%. 6 · Method according to one represents claims 1 to 5 »characterized in that the Kickelgehalt the coated catalyst particles of about 4 to about 7o wt.% By weight. .7 · Fuel cell with an electrolyte chamber with anode and Cathode, which is inserted through a hydrogen permeable membrane the anode is separated from a uta conversion zone in which a nickel-urea conversion catalyst is arranged, thereby characterized in that the catalyst (e.g. 24) comprises particles of a nickel plated refractory material which from about 0.5 # to about 20 J6 of an alkali or alkaline earth metal oxide, hydroxide or carbonate, based on daa weight of metal, or one plated with nickel Alkaline earth oxide contains « 109883/1325