process for producing a ceria-zirconia-alumina composite oxide, ceria-zirconia composite oxide, three-way catalyst, and method for treating a gas from an internal combustion engine

摘要

A process for producing a ceria-zirconia-alumina composite oxide is disclosed. The process comprises combining a cerium (IV) compound and a zirconium (IV) compound with a slurry of aluminum oxide at a temperature greater than 40° C. to produce a reaction slurry, then contacting the reaction slurry with a precipitating agent to precipitate insoluble cerium and zirconium compounds onto the aluminum oxide and form cerium-zirconium-aluminum oxide particles, and calcining the cerium-zirconium-aluminum oxide particles to produce a ceria-zirconia-alumina composite oxide. The process to produce ceria-zirconia-alumina composite oxides provides a material having a high oxygen storage/release capacity that is suitable for a catalyst with enhanced cleaning of the exhaust gases from internal combustion engines.