EXHAUST GAS PURIFYING CATALYST

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PROBLEM TO BE SOLVED : To provide an exhaust gas purifying catalyst capable of highly suppressing HC poisoning of Pd and efficiently purifying NOX in exhaust gas of lean-burn engine by being used as an upstream catalyst of an NOX occluding reducing type catalyst. SOLUTION : The exhaust gas purifying catalyst comprises a carrier containing at least an aluminate of at least one kind of metal M selected from alkali earth metal and rare earth metal and at least Pd deposited on the carrier. The metal M and Pd act efficiently and the HC poisoning of Pd can be effectively suppressed. Further, upon high temperature durability, particle growth of metal M is suppressed and, therefore, the HC poisoning of Pd can be effectively suppressed even after the use at a high temperature. Accordingly, by being used as an upstream catalyst of the NOX occluding reducing type catalyst, a large quantity of HC can be supplied to the NOX occluding reducing type catalyst in the stoichiometric to rich atmosphere.