| 摘要 |
PROBLEM TO BE SOLVED: To produce an exhaust gas cleaning catalyst for efficiently cleaning hydrocarbons (HC) discharged in a low temperature region in the starting up of an engine. SOLUTION: This exhaust gas cleaning catalyst is prepared by laminating an HC storage material layer, a heat resistant inorganic oxide layer and a catalyst component layer on a support to contain γ-alumina in the heat resistant inorganic oxide layer and Ce-(Y)-Ox -supporting Pd or Ce-Al2 O3 -supporting Pd in the catalyst component layer. The heat resistant inorganic layer on the HC storage material layer laminated on the support is arranged on the upstream side in the exhaust gas flowing direction and contains γ-alumina. The catalyst component layer is arranged on the downstream side and contains Ce-(Y)-Ox - supporting Pd or Ce-Al2 O3 -supporting Pd in its 1st layer and Ce-Al2 O3 -supporting Pt, Zr-Al2 O3 -supporting Rh and ZC20, or the like, in its 2nd layer. |
