Method for storing energy in the form of hydrazine carbonate

Patent metadata

Field	Value
Publication number	US-11091845-B2
Application number	US-201716343047-A
Country	US
Kind code	B2
Filing date	Sep 22, 2017
Priority date	Nov 22, 2016
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

Energy storage is accomplished by producing hydrazine carbonate and later reconverting the hydrazine carbonate to release the energy. Sea water is firstly used in an electrolysis process to prepare hypochlorite. The hypochlorite reacts as a result of introduction of ammonia to produce monochloramine and then hydrazine. The hydrazine reacts as a result of introduction of carbon dioxide to give hydrazine carbonate. To release the energy, the hydrazine carbonate liberates hydrogen or at least a hydrogen-containing gas by reaction over a noble metal-free catalyst. The hydrogen may then be enriched before being fed to a fuel cell.

First claim

The invention claimed is:

1. A process for storing energy in the form of hydrazine carbonate and subsequently reconverting the hydrazine carbonate into usable energy,
wherein an electrolysis process uses sea water to prepare hypochlorite, wherein the hypochlorite reacts as a result of introduction of ammonia via the formation of monochloramine to give hydrazine and wherein the hydrazine subsequently reacts as a result of introduction of carbon dioxide to give hydrazine carbonate, and wherein the hydrazine carbonate liberates H 2 or at least a gas containing H 2 by reaction in the presence of a noble metal-free catalyst.

2. The process of claim 1 ,
wherein a separation step for enriching H 2 is provided after the reaction of the hydrazine carbonate in the presence of the noble metal-free catalyst.

3. The process of claim 1 ,
wherein the H 2 or gas containing H 2 is fed to a fuel cell.

4. The process of claim 1 ,
wherein the carbon dioxide is taken from an exhaust gas stream of a combustion plant.

5. The process of claim 1 ,
wherein a catalyst composed of oxidic materials is used as the noble metal-free catalyst.

6. The process of claim 1 ,
wherein the energy used in the sea water electrolysis for preparing hypochlorite is obtained from renewable energy sources.

7. The process of claim 1 ,
wherein the hydrazine carbonate is heated to less than 100° C. by reaction in the presence the noble metal-free catalyst.

8. A process for storing and releasing energy comprising:
storing energy by conducting an electrolysis process to prepare hypochlorite from sea water;
introducing ammonia which reacts with the hypochlorite to form hydrazine;
introducing carbon dioxide which react with the hydrazine to give hydrazine carbonate; and
reacting the hydrazine carbonate in the presence of a noble metal-free catalyst to liberate H 2 or gas containing H 2 .

9. The process of claim 8 , further comprising enriching the hydrogen after the reaction of the hydrazine carbonate in presence of the noble metal-free catalyst.

10. The process of claim 8 , further comprising feeding the H 2 or gas containing H 2 to a fuel cell.

11. The process of claim 8 , wherein the carbon dioxide is taken from an exhaust gas stream of a combustion plant.

12. The process of claim 8 , wherein the noble metal-free catalyst comprises oxidic materials.

13. The process of claim 8 , wherein the hydrazine carbonate is heated to less than 100° C. by reaction in the presence of the noble metal-free catalyst.

Assignees

• Schaeffler Technologies Ag

Inventors

• Holweger Walter
• Wegener Moritz
• Musayev Yashar

Classifications

• Y02P20/133

  Renewable energy sources, e.g. sunlight · CPC title

• C25B15/083

  Separating products · CPC title

• C25B1/04 Primary

  by electrolysis of water · CPC title

• C25B15/08

  Supplying or removing reactants or electrolytes; Regeneration of electrolytes · CPC title

• C07C281/00

  Derivatives of carbonic acid containing functional groups covered by groups C07C269/00 - C07C279/00 in which at least one nitrogen atom of these functional groups is further bound to another nitrogen atom not being part of a nitro or nitroso group · CPC title