Patent ID: 11897783
Assignee: RHODIA OPERATIONS
Field: Chemical engineering (Chemistry)
Classification: CPC C  B | IPC C

Claim 14:
15. A process for preparing a mixed oxide comprising aluminum, cerium, zirconium, lanthanum and optionally at least one rare-earth metal (REM) other than cerium and lanthanum, the process comprising:
(i-a) adding a basic aqueous solution to a dispersion formed from the aluminum hydrate as claimed in claim 1 and an aqueous solution S comprising the salts of cerium, zirconium, lanthanum and optionally at least one rare-earth metal (REM) other than cerium and lanthanum, to precipitate a solid; or
(i-b) adding an aqueous solution S comprising the salts of cerium, zirconium, lanthanum and optionally at least one rare-earth metal (REM) other than cerium and lanthanum to a dispersion formed from the aluminum hydrate as claimed in claim 1 and a basic aqueous solution to precipitate a solid; or
(i-c) adding to a basic aqueous solution a dispersion formed from the aluminum hydrate as claimed in claim 1 and an aqueous solution S comprising the salts of cerium, zirconium, lanthanum and optionally at least one rare-earth metal (REM) other than cerium and lanthanum to precipitate a solid;
(ii) optionally washing the solid obtained at the end of step (i);
(iii) calcining the solid obtained at the end of step (i) or (ii) in air at a temperature of between 700° C. and 1200° C. to obtain the mixed oxide.