| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a catalyst for removing an exhaust gas which has excellent catalytic activities in NO<SB>x</SB>removal. <P>SOLUTION: The catalyst for removing the exhaust gas comprises a first catalyst layer of the exhaust gas upstream side and a second catalyst layer of the exhaust gas downstream side on a substrate, and the first and second catalyst layer contain an NO<SB>x</SB>retention substance. Each layer has the lower layer containing Rh and the upper layer containing Pd and Pt. The concentration of Pd in the first catalyst layer is higher than that in the second layer, and the concentration of Pt in the second catalyst layer is higher than that in the first catalyst layer. <P>COPYRIGHT: (C)2009,JPO&INPIT |
