A catalyst for purifying exhaust gas

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PROBLEM TO BE SOLVED : To provide a catalyst which can efficiently remove contaminants in exhaust gases from various engines included in a wide range of air fuel ratio contg. a lean burn region and has excellent high temp. heat resistance. SOLUTION : In a catalyst for purification of exhaust gas which purifies nitrogen oxides(NOx), carbon monoxide (CO) and hydrocarbons(HC) in the exhaust gas under an excess oxygen atmosphere, a carrier contg. alumina and cerium oxide or an oxide contg. cerium and having oxygen occlusion-releasing characteristics, the first layer (an sublayer) selected from a group consisting of alkali metals, alkaline earth metals and rare earth elements and contg. an NOx occlusion material carried on the carrier and platinum(Pt) carried on the carrier and the second layer (a top layer) contg. alumina and rhodium(Rh) carried on a carrier contg. cerium oxide, zirconium oxide or cerium-zirconium double oxide, are incorporated.