Regeneration method of raw materials for hydrogen supply system of fuel cell

Patent metadata

Field	Value
Publication number	US-9340419-B2
Application number	US-201414552084-A
Country	US
Kind code	B2
Filing date	Nov 24, 2014
Priority date	Dec 20, 2013
Publication date	May 17, 2016
Grant date	May 17, 2016

Abstract

Disclosed is a method and related system of regenerating a raw material for a hydrogen supply system of a fuel cell. The method includes reacting aluminum and a metal hydroxide to produce hydrogen in the hydrogen supply system of a fuel cell; and recovering an aluminum compound produced simultaneously with the hydrogen in the reaction. An aluminum hydroxide is obtained from the aluminum compound. The aluminum hydroxide is heat-treated to obtain an aluminum oxide. The aluminum oxide is reduced to obtain aluminum. The obtained aluminum is re-supplied as a raw material for producing the hydrogen.

First claim

What is claimed is:

1. A method of regenerating a raw material for a hydrogen supply system of a fuel cell, the method comprising steps of:
reacting aluminum and a metal hydroxide to produce hydrogen in a hydrogen supply system of the fuel cell;
recovering a liquid metal aluminum compound produced simultaneously with the hydrogen in the reacting step;
obtaining an aluminum hydroxide from the aluminum compound produced simultaneously with the hydrogen;
heat-treating the aluminum hydroxide to obtain an aluminum oxide;
reducing the aluminum oxide to obtain aluminum; and
re-supplying the obtained aluminum as a raw material for producing hydrogen in the reacting step,
wherein, the reacting step further comprises:
adding aluminum into a metal hydroxide aqueous solution, wherein the concentration of the metal hydroxide in the aqueous solution ranges from about 20 mass % to about 35 mass %, based on a total weight of the metal hydroxide aqueous solution, and wherein about 3.3 to about 7.5 parts by mole of the metal hydroxide is reacted with about 3 parts by mole of the aluminum to suppress the production of precipitate and provide only the liquid metal aluminum compound.

2. The method of claim 1 , wherein the step of reacting aluminum and metal hydroxide to produce hydrogen is performed in a hydrogen supply system of a fuel cell vehicle.

3. The method of claim 1 , wherein the metal hydroxide is a sodium hydroxide.

4. The method of claim 3 , wherein the aluminum compound produced simultaneously with hydrogen is a sodium aluminum hydroxide.

5. The method of claim 4 , wherein the step of obtaining the aluminum hydroxide comprises:
adding carbon dioxide to the sodium aluminum hydroxide to obtain an aluminum hydroxide.

6. The method of claim 5 , further comprising:
simultaneously obtaining a sodium carbonate in the step of adding carbon dioxide into the sodium aluminum hydroxide to obtain an aluminum hydroxide;
obtaining a sodium hydroxide from the sodium carbonate; and
re-supplying the sodium hydroxide as a raw material for producing the hydrogen.

7. The method of claim 1 , wherein the heat-treating step is performed at about 600° C. to about 800° C.

8. The method of claim 7 , wherein the heat-treating step is performed for about 5 to about 15 hours.

9. The method of claim 1 , wherein the reducing step is performed through an electrolyte reduction of the aluminum oxide by adding Ca ions.

10. The method of claim 9 , wherein the electrolyte reduction of the aluminum oxide with Ca ions uses an electrolyte including a CaO.

11. The method of claim 10 , wherein the CaO in the electrolyte has a concentration of about 0.1 to about 1 mass %.

12. The method of claim 9 , wherein the electrolyte reduction of aluminum oxide with Ca ions is represented by the following reaction schemes:
a negative electrode reaction:
primary: Ca 2+ +2 e →Ca

secondary: 3Ca+Al 2 O 3 →3CaO+2Al, and

a positive electrode reaction:
2O 2− →2 e+O 2 .

13. The method of claim 9 , wherein the electrolyte reduction of aluminum oxide with Ca ions is performed at about 400° C. to about 600° C.

14. The method of claim 9 , wherein, in the electrolyte reduction of aluminum oxide with Ca ions, the electrolyte reduction is performed by attaching the aluminum oxide onto a surface of the aluminum.

15. A method of regenerating a raw material for a hydrogen supply system of a fuel cell, the method comprising steps of:
reacting Al and an aqueous solution of NaOH to produce H 2 in a hydrogen supply system of the fuel cell;
recovering a NaAl(OH) 4 liquid produced simultaneously with the H 2 in the reacting step;
precipitating Al(OH) 3 from the recovered NaAl(OH) 4 liquid;
heat-treating the precipitated Al(OH) 3 to obtain Al 2 O 3 ;
reducing the Al 2 O 3 by way of an electrolyte reduction to obtain Al having a surface coated with Al 2 O 3 ; and
re-supplying the obtained Al as a raw material for producing H 2 in the reacting step,
wherein, the reacting step further comprises:
adding Al into an aqueous solution of NaOH, wherein the concentration of the NaOH in the aqueous solution ranges from about 20 mass % to about 35 mass %, based on a total weight of the aqueous solution of NaOH, and wherein about 3.3 to about 7.5 parts by mole of the NaOH is reacted with about 3 parts by mole of the Al to suppress the production of precipitate and provide only the NaAl(OH) 4 liquid.

16. The method of claim 15 , wherein the heat-treating step is performed for about 5 to about 15 hours at about 600 to about 800° C.

17. The method of claim 15 , wherein the reducing of the Al 2 O 3 by way of the electrolyte reduction includes providing Ca ions from an CaO electrolyte.

Assignees

• Hyundai Motor Co Ltd
• Iac In Nat Univ Chungnam
• Iac In Nat Univ Chungnam

Inventors

• Kim Chang Ho
• Hwang Inchul
• Kim Hyung Ki
• Cho Seong Seock
• Lee Jong Hyeon
• Han Moon Hee
• Ryu Hong Youl
• Kim Dae-Young

Classifications

• H01M2250/20

  Fuel cells in motive systems, e.g. vehicle, ship, plane · CPC title

• C01B3/08 Primary

  by reaction of inorganic compounds with metals · CPC title

• H01M8/065

  by dissolution of metals or alloys; by dehydriding metallic substances · CPC title

• Y02E60/50

  Fuel cells · CPC title

• H01M8/0662

  Treatment of gaseous reactants or gaseous residues, e.g. cleaning · CPC title