Catalyst for water gas shift reaction at middle temperature, preparation method thereof, and hydrogen preparation method using same

Patent metadata

Field	Value
Publication number	US-12129174-B2
Application number	US-201917285576-A
Country	US
Kind code	B2
Filing date	Oct 15, 2019
Priority date	Oct 15, 2018
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

The present disclosure provides a catalyst for a water gas shift reaction at middle temperature, the catalyst comprising a catalytically active component containing 40 to 80 mol % of copper (Cu), 15 to 50 mol % of zinc (Zn), and 1 to 13 mol % of aluminum (Al), relative to all metals of the catalyst, wherein an aluminum-rich layer is present in a surface layer of a particle of the catalyst. Furthermore, the present disclosure provides a preparation method of the catalyst, and a hydrogen preparation method using the same.

First claim

The invention claimed is:

1. A method of preparing hydrogen, comprising providing a catalyst for a water gas shift reaction, to perform a water gas shift reaction,
wherein the catalyst for the water gas shift reaction comprises a catalytically active component containing 40 to 80 mol % of copper (Cu), 15 to 50 mol % of zinc (Zn), and 1 to 13 mol % of aluminum (Al), relative to all metals of the catalyst,
wherein an aluminum-rich layer is present in a surface layer of a particle of the catalyst,
wherein the catalyst is prepared by a catalyst preparation method comprising a copper-zinc coprecipitation operation of injecting a metal precursor solution containing a Cu precursor and a Zn precursor into a precipitant solution to coprecipitate copper and zinc, to produce a copper-zinc coprecipitate;
an Al precipitation operation of injecting an Al precursor solution into a solution containing the copper-zinc coprecipitate to precipitate aluminum on a surface of the copper-zinc coprecipitate, to prepare a CuZnAl catalyst precursor material having an aluminum-rich layer on a surface; and
a baking operation of baking the CuZnAl catalyst precursor material to prepare a CuZnAl catalyst,
wherein the copper-zinc coprecipitation operation is performed by aging a mixture of the metal precursor solution containing the Cu precursor and the Zn precursor, and the precipitant solution within a temperature range of room temperature (20° C.) to 80° C. for 30 to 180 minutes,
wherein the Al precursor solution is injected, after a phenomenon after which a pH is reduced to a range of 0.05 to 0.2 and is then returned during the aging.

2. The method of claim 1 , wherein the catalyst is reduced under a hydrogen atmosphere of 280 to 500° C.

3. The method of claim 1 , wherein the water gas shift reaction is carried out under conditions of a reaction temperature of 200 to 450° C. and a molar ratio of water vapor and carbon monoxide of 1.0 to 3.0.

4. The method of claim 1 , wherein the aluminum-rich layer corresponds to 0.1 to 10% of a radius of the particle of the catalyst, from a surface of the particle of the catalyst.

5. The method of claim 1 , wherein the Al precursor solution is injected after the copper-zinc coprecipitate is changed from an amorphous form to a crystalline form during the aging.

6. The method of claim 1 , wherein the Al precipitation operation is performed by injecting the Al precursor solution into the solution containing the copper-zinc coprecipitate and then aging the same within a temperature range of room temperature (20° C.) to 80° C. for 15 to 60 minutes.

7. The method of claim 1 , wherein the metal precursor solution containing the Cu precursor and the Zn precursor has a concentration of 0.01 to 1.5 M, and a molar ratio of Cu ions and Zn ions is 50:50 to 80:20.

8. The method of claim 1 , wherein the Cu precursor, the Zn precursor, and the Al precursor are salts having at least one anion selected from the group consisting of NO 3 − , SO 4 2− , CH 3 COO − , HCOO − , Cl − , and I − .

9. The method of claim 1 , wherein the metal precursor solution containing the Cu precursor and the Zn precursor is injected into the precipitant solution until a pH is 5 to 8.

10. The method of claim 1 , wherein the precipitant is at least one precipitant selected from the group consisting of alkali metal, carbonate or bicarbonate of Li, Na, K, or ammonium, NaOH, and NH 4 OH.

11. The method of claim 1 , wherein the precipitant solution has a temperature range of room temperature (20° C.) to 80° C., and a pH of 6 to 9.

12. The method of claim 1 , wherein the precipitant solution has a concentration of 0.01 to 1.2 M.

13. The method of claim 1 , wherein a concentration of the Al precursor solution is 0.01 to 1.5 M.

14. The method of claim 1 , wherein the Al precursor solution is injected until a pH is 5 to 7.

15. The method of claim 1 , wherein the catalyst preparation method further comprises:
a filtration and washing operation of filtering and washing a solution containing the CuZnAl catalyst precursor material obtained in the Al precipitation operation to obtain a CuZnAl catalyst precursor material; and
a drying operation of drying the obtained CuZnAl catalyst precursor material in an oven within a temperature range of 100 to 300° C. for 22 to 24 hours.

16. The method of claim 1 , wherein the catalyst preparation method further comprises a reduction operation of performing a reduction reaction of the CuZnAl catalyst under a hydrogen atmosphere of 280 to 500° C.

Assignees

• Res Inst Ind Science & Tech
• Iucf Hyu

Inventors

• Kim Joon-Woo
• Suh Young-Woong
• Koh Dong-Jun
• Jeong Cheon-Woo

Classifications

• B01J35/19

  Catalysts containing parts with different compositions · CPC title

• C01B2203/1088

  Non-supported catalysts · CPC title

• C01B2203/1076

  Copper or zinc-based catalysts · CPC title

• C01B2203/0283

  containing a CO-shift step, i.e. a water gas shift step · CPC title

• B01J37/18

  with gases containing free hydrogen · CPC title