COMPOSITE OXIDE FOR EXHAUST-CLEANING CATALYST, METHOD OF MANUFACTURING THE SAME, PAINT FOR EXHAUST-CLEANING CATALYST AND FILTER FOR CLEANING DIESEL EXHAUST

摘要

PROBLEM TO BE SOLVED: To provide a composite oxide for exhaust-cleaning catalyst which is capable of burning PM in diesel engine exhaust at a low temperature and is excellent in S-releasing property.;SOLUTION: The composite oxide for exhaust-cleaning catalyst is composed of Ce, Bi, Pr, R and oxygen and, when molar ratios of Ce, Bi, Pr and R are presented by Ce/Bi/Pr/R=(1-x-y-z)/x/y/z, satisfies the following relations: 0x+y+z0.5 and, preferably, 0x0.1, 0y0.25 and 0z0.3. In particular, the composite oxide for exhaust-cleaning catalyst when R is Zr is excellent in S-releasing property at a temperature of the extent of 600C and can revive the catalytic activity at a low temperature and, therefore, the exhaust-cleaning catalyst can be used suitably as a PM-burning catalyst.;COPYRIGHT: (C)2010,JPO&INPIT