Patent ID: 8337791

Claim:
An exhaust gas purification catalyst, characterized in that a catalyst composition for purifying hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NO x ) contained in exhaust gas is coated onto a honeycomb type structure with at least the upper and lower two layers as follows: <The Upper Layer> A catalyst composition comprising an activated metal (A), a heat resistant inorganic oxide (B) and a cerium-zirconium-type composite oxide (C) containing a pyrochlore phase in a crystal structure, wherein the activated metal (A) is rhodium; <The Lower Layer> A catalyst composition comprising an activated metal (A), a heat resistant inorganic oxide (B) and a cerium-containing oxide (C′) having a cubic crystal and/or a tetragonal crystal as a major crystal structure, wherein the activated metal (A) is palladium, or palladium and platinum.