Method of producing hydrogen

Patent metadata

Field	Value
Publication number	US-10472234-B2
Application number	US-201415025843-A
Country	US
Kind code	B2
Filing date	Sep 30, 2014
Priority date	Sep 30, 2013
Publication date	Nov 12, 2019
Grant date	Nov 12, 2019

Abstract

The present invention relates to a method of producing hydrogen from ammonia, and in particular a method of producing hydrogen from ammonia for use in a fuel cell and/or in a prime mover. The method may be carried out in-situ in a vehicle. The invention also relates to an apparatus for producing hydrogen from ammonia.

First claim

The invention claimed is:

1. A method of producing hydrogen from ammonia, the method comprising:
(i) providing ammonia as a fuel source;
(ii) introducing ammonia into a reactor;
(iii) contacting at least some of the ammonia in the reactor with a metal-containing-compound to form hydrogen;
(iv) removing at least some of the hydrogen formed in step (iii); and
(v) contacting the metal-containing-compound with further ammonia;
wherein the metal-containing-compound comprises one or more of Li, Be, Mg, Ca, Sr, Ba or alloys or mixtures of two or more thereof;
wherein the metal-containing-compound is selected from a metal amide, metal imide, metal nitride or combinations thereof; and
wherein the metal-containing-compound is regenerated prior to step (v).

2. The method according to claim 1 , wherein the metal-containing-compound comprises one or more of Li, Be, Ca, Sr, Ba or alloys or mixtures of two or more thereof.

3. The method according to claim 1 , wherein the metal-containing-compound comprises Li or alloys thereof.

4. The method of claim 1 , wherein the metal-containing-compound comprises Be, Mg, Ca, Sr, Ba or alloys or mixtures of two or more thereof.

5. The method of claim 4 , wherein the metal-containing-compound comprises Ca, Mg or alloys or mixtures of two or more thereof.

6. The method according to claim 1 , wherein the metal-containing-compound is selected from a metal imide or metal nitride or combinations thereof.

7. The method according to claim 3 , wherein the metal-containing-compound is a metal imide.

8. The method according to claim 1 , wherein the metal-containing-compound comprises Li; and the metal-containing-compound is selected from a metal imide or metal nitride or combinations thereof.

9. The method according to claim 1 , wherein the metal-containing-compound is provided by thermally decomposing a metal-containing-compound precursor.

10. The method according to claim 9 , wherein the metal-containing-compound precursor is a metal amide.

11. The method according to claim 1 , wherein step (iii) is carried out at a temperature in the range of from −30 to 800° C.

12. The method according to claim 1 , wherein step (iii) is carried out at a temperature in the range of from 400 to 440° C.

13. The method according to claim 1 , wherein step (iii) is carried out at a pressure in the range of from 0.05 to 20 MPa.

14. The method according to claim 1 , wherein step (iii) is carried out at a pressure in the range of from 0.1 to 0.2 MPa.

15. The method according to claim 1 , wherein ammonia is introduced into the reactor at a temperature in the range of from −30 to 800° C.

16. The method according to claim 1 , wherein ammonia is introduced into the reactor at a temperature in the range of from 400 to 440° C.

17. The method according to claim 1 , wherein ammonia is introduced into the reactor at a pressure in the range of from 0.05 to 20 MPa.

18. The method according to claim 1 , wherein ammonia is introduced into the reactor at a pressure in the range of from 0.1 to 0.2 MPa.

19. The method according to claim 1 , wherein the molar ratio of metal-containing-compound to ammonia is in the range of from 1:1 to 2:1.

20. The method according to claim 1 wherein the method is carried out in-situ in a vehicle.

21. The method according to claim 1 , further comprising introducing the removed hydrogen into a fuel cell or a prime mover.

22. The method according to claim 1 , further comprising combusting the removed hydrogen.

23. The method according to claim 1 , wherein the ammonia is in a gaseous and/or liquid state.

24. The method according to claim 1 , wherein ammonia is introduced into the reactor by injection, pumping, spraying and/or by mechanical means.

25. The method according to claim 1 , further comprising refuelling the ammonia fuel source.

26. The method according to claim 1 , wherein the metal-containing-compound is in the faun of a solid, liquid or dispersed form.

27. The method according to claim 1 , wherein step (iii) is carried out in the absence of a catalyst.

28. The method according to claim 1 , wherein step (iii) is carried out in the presence of a catalyst.

29. The method according to claim 28 , wherein the catalyst comprises one or more transition metals, lanthanide metals and mixtures thereof.

30. The method according to claim 29 , wherein the catalyst is selected from the group consisting of transition metal calogenides, lanthanide metal calogenides, transition metal halides, lanthanide metal halides, transition metal pnictides, lanthanide metal pnictides, transition metal tetrels, lanthanide metal tetrels and mixtures of two or more thereof.

31. The method according to claim 1 , wherein the metal-containing-compound and/or a precursor thereof is introduced into the reactor.

32. The method according to claim 31 , wherein the metal-containing-compound and/or a precursor thereof is introduced into the reactor by pumping (preferably electromotively), spraying, or is mechanically introduced.

33. The method according to claim 1 , further comprising removing hydrogen formed by the contacting of ammonia with the metal-containing-compound from the reactor.

34. The method according to claim 1 , wherein the metal imide includes stoichiometric and/or non-stoichiometric imides of the formula M(3-a)NHa where 1≤a <2 when M is Li and of the formula M(NHb)b where 1≤b<2 when M is one or more of Be, Mg, Ca, Sr, Ba.

Assignees

• The Science And Tech Facilities Council
• Res & Innovation Uk

Inventors

• Jones Martin Owen
• David William Ian Fraser
• Makepeace Joshua William

Classifications

• C01B21/08

  Hydrazoic acid; Azides; Halogen azides · CPC title

• C01B3/08

  by reaction of inorganic compounds with metals · CPC title

• H01M8/1018

  Polymeric electrolyte materials · CPC title

• C01B3/047 Primary

  Decomposition of ammonia · CPC title

• H01M2300/0082

  Organic polymers · CPC title