EXHAUST GAS PURIFICATION CATALYST

摘要

Provided is a novel exhaust gas purification catalyst having high gas diffusion/ mixing properties in the catalyst layer, which can thereby exhibit exceptional catalytic performance. Proposed is an exhaust gas purification catalyst provided with a catalyst layer having two or more types of inorganic porous particles of different particle size, a catalytically active component, and voids, wherein the exhaust gas purification catalyst is characterized firstly in that 50% or more of the total number of voids in the catalyst layer satisfy the condition of the following (formula 1), and characterized secondly in that the average void radius in the void cross-sectional area of the catalyst layer, calculated on the assumption of a true circle, is 10 μm-2- μm. L/2/(&pgr;S)1/2≧2 … (formula 1) S: Void cross-sectional area, L: Length of void cross sectional circumference