| 摘要 |
<P>PROBLEM TO BE SOLVED: To enhance the heat resistance and oxygen occlusion capacity of a catalyst for purification of exhaust gas so as to keep high exhaust gas purifying performance even in small amounts of the catalytic noble metal and attempt cost reduction. <P>SOLUTION: The catalyst has a catalyst layer 6 comprising a composite oxide containing Ce, Zr, a metal ingredient M and a catalytic noble metal, and activated alumina, and formed on the surface of the cell wall 5 of a honeycomb-shaped support. The CeO<SB>2</SB>/ZrO<SB>2</SB>mass ratio of the composite oxide is lower than 1, and the ratio of the oxide MO<SB>x</SB>of the metal ingredient M, or MO<SB>x</SB>/(CeO<SB>2</SB>+ZrO<SB>2</SB>+MO<SB>x</SB>), is ≤7 mass%. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
