EXHAUST GAS PURIFICATION CATALYST AND EXHAUST GAS PURIFICATION METHOD

摘要

PROBLEM TO BE SOLVED: To efficiently perform the purification of NOin the wide temperature range of exhaust gas.SOLUTION: Provided is an exhaust gas purification catalyst comprising: a lower layer 3a formed on a carrier base material 2 and also including an inorganic oxide having NOadsorption/occlusion performance and a Ce-containing oxide; and an upper layer 3b formed on the lower layer 3a and also including active alumina, and at least one catalyst metal selected from Pt and Rh and a catalyst carried with an NOocclusion material are arranged at the lower layer 3a and the upper layer 3b in the exhaust gas passage of an engine.