| 摘要 |
<P>PROBLEM TO BE SOLVED: To increase SO<SB>x</SB>occlusion amount of an occlusion catalyst disposed at an upstream side of NO<SB>x</SB>occlusion reduction catalyst, and to increase NO<SB>x</SB>occlusion amount in a low temperature region. <P>SOLUTION: The occlusion catalyst 3 comprises: a carrier base material 30 which is formed of at least one member selected from among Al<SB>2</SB>O<SB>3</SB>, CeO<SB>2</SB>, ZrO<SB>2</SB>, TiO<SB>2</SB>and zeolite and has a specific area of 30 m<SP>2</SP>/g or more; and a coat layer 31 formed by carrying occlusion material occluding NO<SB>x</SB>and SO<SB>x</SB>and a noble metal on carrier powder comprising at least one member selected from among Al<SB>2</SB>O<SB>3</SB>, CeO<SB>2</SB>, ZrO<SB>2</SB>, TiO<SB>2</SB>and zeolite. The large specific area of the carrier base material 30 greatly increases the carrying amount of occlusion material occluding NO<SB>x</SB>and SO<SB>x</SB>. <P>COPYRIGHT: (C)2008,JPO&INPIT |
