US 2014/0179515 A1 · COMPLEX OXIDE, METHOD FOR PRODUCING SAME, AND EXHAUST GAS PURIFICATION CATALYST

Abstract

Provided are: a complex oxide that exhibits high redox ability even at low temperatures, has excellent heat resistance, and stably retains these characteristics even on repeated oxidation and reduction at high temperature; a method for producing the same; and an exhaust gas purification catalyst. The inventive complex oxide contains more than 0 but no more than 20 parts by mass of Si, calculated as SiO2, per total 100 parts by mass of rare earth metal elements including Ce, calculated as oxides; and has a characteristic such that when it is subjected to temperature-programmed reduction (TPR) measurement in a 10% hydrogen-90% argon atmosphere at from 50° C. to 900° C. with the temperature increasing at a rate of 10° C./min, followed by oxidation treatment at 500° C. for 0.5 hours, and then temperature-programmed reduction measurement is performed again, its calculated reduction rate at and below 400° C. is at least 1.5%.

Claims20

Dependent claims

A complex oxide containing more than 0 parts by mass but no more than 20 parts by mass of silicon, calculated as SiO2, per total 100 parts by mass of rare earth metal elements including cerium, calculated as oxides;

wherein the complex oxide has, subsequent to reduction treatment in a 10% hydrogen-90% argon atmosphere between 50° C. and 900° C. with temperature increasing at 10° C./min, followed by oxidation treatment at 500° C. for 0.5 hours, a calculated reduction rate at and below 400° C. of at least 1.5% as measured by temperature-programmed reduction (TPR) in a 10% hydrogen-90% argon atmosphere between 50° C. and 900° C. with temperature increasing at 10° C./min.

Dependencies are inferred from the claim text.

Complex oxide, method for producing same, and exhaust gas purification catalyst

Life of this patent

Complex oxide, method for producing same, and exhaust gas purification catalyst

Life of this patent

Abstract

Claims20