EXHAUST GAS PURIFICATION CATALYST

摘要

The exhaust gas purification catalyst according to the present invention has a substrate 54, a lower layer 57 disposed on this substrate 54, and an upper layer 58 disposed on this lower layer 57. The upper layer 58 is provided with a first catalyst and a second catalyst, and the lower layer 57 is provided with a first catalyst. This first catalyst has Al 2 O 3 as a carrier and Pt and Pd as noble metals supported on the Al 2 O 3 , while the second catalyst typically has an Al 2 O 3 -ZrO 2 -TiO 2 complex oxide as a carrier and has Pd as a noble metal supported on the Al 2 O 3 -ZrO 2 -TiO 2 complex oxide. Moreover, the upper layer 58 has a hydrocarbon adsorbent 68.