Patent ID: 7956005

Claim:
An exhaust gas-purifying catalyst comprising: a particulate composite oxide catalyst containing a rare-earth element, an alkaline-earth element and a precious metal, a part of the rare-earth element and a part of the alkaline-earth element forming a composite oxide, and the composite oxide and a part of the precious metal forming a solid solution; and a particulate refractory support supporting the particulate composite oxide catalyst and including at least one composite oxide selected from the group consisting of a first composite oxide represented by a general formula AB 2 O 4 , and a second composite oxide having a pyrochlore structure represented by a general formula X 2 Y 2 O 7 , the element A being alkaline-earth element and/or transition metal element, the element B being at least one element selected from the group consisting of aluminum, magnesium and transition metal elements and differing from the element A, the element X being rare-earth element, the element Y being zirconium and/or titanium, and the particulate composite oxide catalyst and the particulate refractory support forming a mixture wherein a ratio of the precious metal forming the solid solution with respect to the whole precious metal falls within a range from 10% to 80%.