| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the catalyst poisoning of a waste gas cleaning catalyst due to sulfur discharged from an internal combustion engine operated in an oxidation atmosphere. <P>SOLUTION: The subject waste gas cleaning catalyst is composed of a carrier base material 2, an NO<SB>X</SB>-cleaning catalyst layer 3 of an NO<SB>X</SB>capture/reduction type applied on the carrier base material and a sulfur catching layer 4 containing Mn and Zr, which is applied on the NO<SB>X</SB>-cleaning catalyst layer. In the subject waste gas cleaning method, the waste gas cleaning catalyst is disposed on a waste gas passage of the internal combustion engine operated in the oxidation atmosphere and, when the NO<SB>X</SB>-cleaning performance is degraded, waste gas is temporarily switched to a reduction atmosphere, and thereafter, is returned to the oxidation atmosphere again. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
