| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an oxidation catalyst for cleaning exhaust gas, which has an excellent function of oxidizing particulates and high boiling point substances such as polycyclic aromatic compounds, both of which are contained in the exhaust gas from an internal-combustion engine. <P>SOLUTION: The oxidation catalyst comprises a mixed crystal structure of a compound oxide of metallic elements A, B which is shown by ABO<SB>3</SB>, an oxide of a metallic element A which is shown by A<SB>2</SB>O<SB>3</SB>and an oxide of a metallic element B which is shown by B<SB>2</SB>O<SB>3</SB>. The ratio of (the ionic radius of the metallic element A)/(that of the metallic element B) is within 1.349-1.580. The metallic element B having the smaller ionic radius is Mn and the metallic element A having the larger ionic radius is one metallic element selected from the group consisting of Sc, Y, Ho, Er, Tm, Yb and Lu. The compound oxide has a hexagonal structure. Each of the oxide of the metallic element A and the oxide of the metallic element B has a C-rare earth structure. <P>COPYRIGHT: (C)2008,JPO&INPIT |
