Honeycomb catalytic structure, precoated support for producing honeycomb catalytic structure, and process for producing honeycomb catalytic structure

A honeycomb catalytic structure comprising:

• a honeycomb structure comprising porous partition walls having a large number of pores, disposed so as to form a plurality of cells extending between two end faces of the honeycomb structure and plugging portions disposed at either one end of each cell, and
• a catalyst layer containing a catalyst, supported at least on inner surfaces of the pores of the honeycomb structure,
• wherein the catalyst layer is made of particles and a 50% particle diameter (D50) of the particles is greater than or equal to 1.7 μm and is 70% or less of an average pore diameter of the pores, wherein the average pore diameter is greater than or equal to 50 μm but not more than 500 μm and
• at least part of inner surfaces of pores of the porous partition walls having a large number of pores, disposed so as to form a plurality of cells extending between two end faces of the honeycomb structure, are coated with a substance containing no noble metal.

A honeycomb catalytic structure comprising:

• a honeycomb structure comprising porous partition walls having a large number of pores, disposed so as to form a plurality of cells extending between two end faces of the honeycomb structure and plugging portions disposed at either one end of each cell, and
• a catalyst layer containing a catalyst, supported at least on inner surfaces of the pores of the honeycomb structure,
• wherein the catalyst layer is made of particles and the 90% particle diameter (D90) of the particles is greater than or equal to 5.2 μm and is 100% or less of the average pore diameter of the pores, wherein the average pore diameter is greater than or equal to 50 μm but not more than 500 μm, and
• at least part of inner surfaces of pores of the porous partition walls having a large number of pores, disposed so as to form a plurality of cells extending between two end faces of the honeycomb structure, are coated with a substance containing no noble metal.