Patent ID: 9347357
Filing Date: 2016-05-24
CPC Classification: B01D,B01J,F01N

Claim Text:
1. A honeycomb catalyst body comprising: a honeycomb structure having porous partition walls with which a plurality of cells extending from an inflow side end surface to an outflow side end surface are defined and formed to become through channels of an exhaust gas; outflow side plugged portions arranged in open frontal areas of the predetermined cells in the outflow side end surface, to form the inflow cells which are open in the inflow side end surface and are closed in the outflow side end surface; inflow side plugged portions arranged in open frontal areas of the remaining cells in the inflow side end surface, to form the outflow cells which are open in the outflow side end surface and are closed in the inflow side end surface; and porous catalyst layers formed on the surfaces of the partition walls on the side of the outflow cells, and having a catalyst to purify the exhaust gas, wherein in the honeycomb structure, the inflow cells and the outflow cells are alternately arranged via the partition walls, and the plurality of cells are formed so that, prior to forming the porous catalyst layers, an open area of each of the outflow cells in a cross section of the outflow cell perpendicular to an extending direction of the cells is larger than an open area of each of the inflow cells in a cross section of the inflow cell perpendicular to the extending direction of the cells, wherein a porosity of the partition walls of the honeycomb structure is from 25 to 55%, wherein the catalyst layers are not formed on the surfaces of the partition walls on the side of the inflow cells, and wherein the catalyst layers are not formed on the surfaces of the pores in the partition walls, or even when the catalyst layers are formed on the surfaces of the pores in the partition walls, a total area of the catalyst layers formed on the surfaces of the pores in the partition walls is 5% or less of a total area of the pores in the partition walls, in a cross section parallel to the extending direction of the cells.