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This method for hydrogen production from ammonia is based on the catalytic dissociation of gaseous ammonia in a cracker. A catalytic fixed bed is used. The ammonia cracker supplies a fuel cell (for example, an alkaline fuel cell AFC) with a mixture of hydrogen and nitrogen. Most of the supplied hydr

This method for hydrogen production from ammonia is based on the catalytic dissociation of gaseous ammonia in a cracker. A catalytic fixed bed is used. The ammonia cracker supplies a fuel cell (for example, an alkaline fuel cell AFC) with a mixture of hydrogen and nitrogen. Most of the supplied hydrogen is burned in the ammonia cracker for the supply of the energy needed for the ammonia dissociation process.

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1. A process for producing a hydrogen and nitrogen mixture from gaseous ammonia, said process comprising:(a) providing a gaseous ammonia stream to a dissociation unit of an ammonia cracker to dissociate the gaseous ammonia stream to a mixture of hydrogen and nitrogen at a temperature of about 500° C

1. A process for producing a hydrogen and nitrogen mixture from gaseous ammonia, said process comprising:(a) providing a gaseous ammonia stream to a dissociation unit of an ammonia cracker to dissociate the gaseous ammonia stream to a mixture of hydrogen and nitrogen at a temperature of about 500° C. to 750° C., wherein the dissociation unit consists essentially of a catalyst bed containing aluminum oxide pellets onto which an active catalyst metal has been deposited , the active catalyst metal being a member selected from the group consisting of nickel, ruthenium and platinum; (b) supplying the hydrogen and nitrogen mixture to a fuel cell, and (c) feeding a portion of hydrogen electrode off gas of the fuel cell to a heating unit of the ammonia cracker to supply heat for further dissociation reactions of the ammonia. 2. The process according to claim 1, further comprising vaporizing liquid anhydrous ammonia to produce gaseous ammonia for said gaseous ammonia stream.3. The process according to claim 1, wherein the hydrogen and nitrogen mixture is supplied to an alkaline fuel cell.4. The process according to claim 1, wherein the heating unit comprises a catalytic burner to convert a portion of the hydrogen electrode off gas into heat.5. The process according to claim 1, wherein the heating unit comprises a lean gas combustor to convert a portion of the hydrogen electrode off gas into heat.6. The process according to claim 1, wherein gaseous ammonia is used at a pressure of up to 2 bar.7. The process according to claim 1, wherein dissociation of the gaseous ammonia stream in the ammonia cracker proceeds with a start up time and wherein the ammonia cracker is configured to operate at 1 kW.8. The process according to claim 1 utilizing a three plate rectangular cracker having said three plates positioned within the cracker so as to control ammonia flow within the cracker.9. The process according to claim 2, wherein the liquid anhydrous ammonia is vaporized in an ammonia preheating unit.10. The process according to claim 9, wherein an ammonia/hydrogen/nitrogen mixture produced by said ammonia preheating unit is provided to the heating unit of the ammonia cracker during start up time.11. The process according to claim 1, wherein said hydrogen electrode off gas is used as combustible in said heating unit to create said heat.