Patent ID: 9597660
Date: 2017-03-21
CPC Classifications: B01D,B01J,Y02C,Y02T

Claim:
1. A catalytic converter comprising: a base material having a cellular structure through which exhaust gases flow; and a catalyst layer formed on a surface of a cell wall in the base material, wherein the catalyst layer has a lower catalyst layer and an upper catalyst layer, the lower catalyst layer is formed on a surface of the base material along an entire length of the base material, the upper catalyst layer is constituted by a first upper catalyst layer and a second upper catalyst layer, the first upper catalyst layer is formed on an upstream side of a surface of the lower catalyst layer in a direction of exhaust gas flow, an upstream side end of the base material is a starting point of the first upper catalyst layer, the second upper catalyst layer is formed on a downstream side of the surface of the lower catalyst layer in the direction of the exhaust gas flow, a downstream side end of the base material is a starting point of the second upper catalyst layer, the lower catalyst layer is formed of a carrier and palladium supported on the carrier, the first upper catalyst layer is formed of a first carrier and rhodium supported on the first carrier, the first carrier is formed of a complex oxide comprising Al the second upper catalyst layer is formed of a second carrier and rhodium supported on the second carrier, the second carrier being formed of a complex oxide comprising Al a length of the first upper catalyst layer in the direction of the exhaust gas flow is 30 to 70% of an overall length of the base material, and a length of the second upper catalyst layer in the direction of the exhaust gas flow is a length obtained by subtracting the length of the first upper catalyst layer from the overall length of the base material, wherein the first carrier is formed of a ceria-containing zirconia complex oxide, and the second carrier is formed of a zirconia complex oxide that does not contain ceria.