Patent ID: 11904298
Assignee: NGK INSULATORS, LTD.
Field: Chemical engineering (Chemistry)
Classification: CPC B  F | IPC B  F

Claim 7:
8. A method of producing a composite oxide catalyst according to claim 1, comprising:
preparing a mixed aqueous solution by mixing a nitrate of a raw metal and citric acid;
obtaining a precursor by heating said mixed aqueous solution; and
obtaining a composite oxide catalyst by firing said precursor,
wherein said raw metal includes cerium that is a first metal, lanthanum that is a second metal, and a third metal,
said third metal is a transition metal, or a rare-earth metal other than cerium and lanthanum,
a cerium content in said raw metal is higher than or equal to 5 mol % and lower than or equal to 95 mol %,
a lanthanum content in said raw metal is higher than or equal to 2 mol % and lower than or equal to 93 mol %, and
a content of said third metal in said raw metal is higher than or equal to 2 mol % and lower than or equal to 93 mol %.