INORGANIC OXIDE AND EXHAUST GAS CLEANING CATALYST USING THE SAME

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PROBLEM TO BE SOLVED : To provide an inorganic oxide having excellent heat resistance. SOLUTION : The particulate inorganic oxide contains aluminum oxide, a metal oxide which does not form a compound oxide with aluminum oxide, and at least one additional element selected from the group composed of rare earth elements and alkaline-earth elements. This inorganic oxide is characterized in that the content of the additional element is 1.1-8.0 atomic% of the total amount of aluminum of the aluminum oxide, a metallic element of the metal oxide and the additional element in terms of elements, ≥80% of primary particles of the inorganic oxide have each ≤100 nm particle size, at least a part of the primary particle of the inorganic oxide has an additional element-concentrated surface zone, where the content of the additional element is made higher locally, in the surface layer part, and the amount of the additional element in the additional element-concentrated surface zone is 0.06-0.98 mass% of the total amount of the inorganic oxide in terms of oxides. COPYRIGHT : (C)2008, JPO&INPIT