Catalyst for production of hydrogen and process for producing hydrogen using the catalyst, and catalyst for combustion of ammonia, process for producing the catalyst and process for combusting ammonia using the catalyst

Abstract

Disclosed is a catalyst which can be used in the process for producing hydrogen by decomposing ammonia, can generate heat efficiently in the interior of a reactor without requiring excessive heating the reactor externally, and can decompose ammonia efficiently and steadily by utilizing the heat to produce hydrogen. Also disclosed is a technique for producing hydrogen by decomposing ammonia efficiently utilizing the catalyst. Specifically disclosed is a catalyst for use in the production of hydrogen, which is characterized by comprising an ammonia-combusting catalytic component and an ammonia-decomposing catalytic component. Also specifically disclosed is a catalyst for use in the production of hydrogen, which is characterized by comprising at least one metal element selected from the group consisting of cobalt, iron, nickel and molybdenum.

Description

TECHNICAL FIELD[0001]The present invention relates to a catalyst used for producing hydrogen using ammonia as a raw material and a process for producing hydrogen using the catalyst. The present invention also relates to a catalyst used for combusting ammonia existing in air or high concentration ammonia contained in an industrial waste gas, etc. at low temperature, a process for producing the catalyst and a process for combusting ammonia using the catalyst.BACKGROUND ART[0002]With respect to techniques for production of hydrogen, there are by-product hydrogen from other industrial processes, e.g., from processes manufacturing iron and steel, hydrogen produced by reforming coal and petroleum, etc. Hydrogen produced by such processes is strongly equipment-dependent and lack of convenience in the aspect of simple utilization thereof at proper timing.[0003]On the other hand, as a means for easily obtaining hydrogen, there is a method of utilizing a decomposition reaction of ammonia. The...

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Benefits of technology

[0026]The present invention can provide a cheap and practical catalyst for a process for obtaining hydrogen by decomposition of ammonia, which can promote a self-directing reaction by combusting a portion of ammonia and utilizing the obtained combustion heat for decomposition of ammonia without using excess heat from the outside of a reactor and efficiently produce hydrogen from ammonia. Further, the present invention can also provide a technique of efficiently producing hydrogen from ammonia by using the catalyst. In addition, the present invention can provide a catalyst for combustion of ammonia excellent in practical applicability which has the same ammonia combustion activity as that of a noble metal-based catalyst without using any costly noble metal element, a process for producing the catalyst, and a process for combusting ammonia using this catalyst.

Problems solved by technology

Hydrogen produced by such processes is strongly equipment-dependent and lack of convenience in the aspect of simple utilization thereof at proper timing.

However, in the case of using these catalysts, it is difficult to control the reaction in accordance with the catalyst composition and it is not easy sometimes to steadily obtain hydrogen in a constant concentration.

Further, due to alteration of catalyst layer temperature, an ammonia reformer may possibly be damaged or the catalysts may possibly be deteriorated.

Due to these factors, the ammonia decomposition reaction becomes unstable.

If the decomposition ratio is insufficient, a large quantity of ammonia remains in the gas after the reaction and it results in provision of a fuel with an inferior quality as a hydrogen fuel.

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