Catalyst compositions for ammonia decomposition

Patent metadata

Field	Value
Publication number	US-11806700-B2
Application number	US-202217944623-A
Country	US
Kind code	B2
Filing date	Sep 14, 2022
Priority date	Feb 4, 2020
Publication date	Nov 7, 2023
Grant date	Nov 7, 2023

Abstract

A method for ammonia decomposition to produce hydrogen, the method comprising the steps of introducing an ammonia stream to a reactor, wherein the ammonia stream comprises ammonia, wherein the reactor comprises a cobalt-based catalyst, the cobalt-based catalyst comprising 15 wt % and 70 wt % of cobalt, 5 wt % and 45 wt % of cerium, and 0.4 wt % and 0.5 wt % barium, wherein a remainder of weight of the cobalt-based catalyst is oxygen; contacting the ammonia in the ammonia stream with the cobalt-based catalyst, wherein the cobalt-based catalyst is operable to catalyze an ammonia decomposition reaction; catalyzing the ammonia decomposition reaction to cause the ammonia decomposition in the presence of the cobalt-based catalyst to produce hydrogen; and withdrawing a product stream from the reactor, the product stream comprising hydrogen.

First claim

That which is claimed is:

1. A cobalt-based catalyst composition, the cobalt-based catalyst composition comprising:
15 wt % and 70 wt % of cobalt;
5 wt % and 45 wt % of cerium; and
0.4 wt % and 0.5 wt % barium,
wherein a remainder of weight of the cobalt-based catalyst is oxygen.

2. The cobalt-based catalyst composition of claim 1 , comprising cobalt oxide.

3. The cobalt-based catalyst composition of claim 1 , comprising cerium oxide.

4. The cobalt-based catalyst composition of claim 1 , wherein the cobalt is an active metal.

5. The cobalt-based catalyst composition of claim 1 , wherein the cerium is operable to act as a support and as a promoter.

6. A method of preparing a cobalt-based catalyst, the method comprising the steps of:
dissolving cobalt nitrate hexahydrate (Co(NO 3 )⋅6H 2 O) and cerium nitrate hexahydrate (Ce(NO 3 )⋅6H 2 O) in distilled water;
adding a sodium carbonate (Na 2 CO 3 ) solution;
maintaining the solution until cobalt and cerium carbonates precipitate from the solution;
filtering the cobalt and cerium carbonates under pressure of about 0.4 bar;
washing the filtered cobalt and cerium carbonates using cold distilled water until the pH is 7 to produce the washed precipitate;
drying the washed precipitate at a temperature of 100° C. for at least 8 hours to produce a dried precipitate;
calcining the dried precipitate at a temperature of 550° C. for at least 3 hours to produce a black powder, wherein the temperature of the calcining step is operable to burn out the carbonate to produce the black powder comprising a composite oxide of Co 3 O 4 /CeO 2 ;
impregnating the black powder with an aqueous solution of barium nitrate (Ba(NO 3 ) 2 ) to produce a precursor;
drying the precursor at a temperature of 120° C. for at least 8 hours to produce a dried precursor; and
calcining the dried precursor at a temperature of 550° C. for at least 3 hours to produce the cobalt-based catalyst, where the cobalt-based catalyst comprises:
15 wt % and 70 wt % of cobalt,
5 wt % and 45 wt % of cerium, and

0.4 wt % and 0.5 wt % barium, wherein a remainder of weight of the cobalt-based catalyst is oxygen.

7. The method of claim 6 , further comprising the steps of crushing the cobalt-based catalyst to produce particles of the cobalt-based catalyst;
sieving the particles; and
collecting the particles of the cobalt-based catalyst with a diameter between 0.3 mm and 0.5 mm.

Assignees

• Saudi Arabian Oil Co
• Univ King Abdullah Sci & Tech

Inventors

• Gascon Jorge
• Sayas Salvador
• Morlanes Natalia
• Katikaneni Sai
• Harale Aadesh
• Solami Bandar

Classifications

• B01J2235/15

  X-ray diffraction · CPC title

• B01J35/45

  Nanoparticles · CPC title

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J35/40

  characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77) · CPC title