INORGANIC OXIDE, CATALYST CARRIER FOR CLEANING EXHAUST GAS AND CATALYST FOR CLEANING EXHAUST GAS

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PROBLEM TO BE SOLVED : To provide an inorganic oxide in which grain growth of carried metals (rhodium, or the like) is sufficiently suppressed, a catalyst carrier for cleaning an exhaust gas comprising the same and a catalyst for cleaning the exhaust gas using the same. SOLUTION : The granular inorganic oxide contains aluminum oxide; a metal oxide not forming a composite oxide with aluminum oxide; and an addition element comprising at least one of a rare-earth element and an alkaline earth element and contains a secondary particle formed by coagulation of a primary particle. In the inorganic oxide, at least a part of the secondary particle is formed by coagulation of a plurality of the first primary particles with a particle diameter of 100 nm or less containing aluminum oxide and the addition element and a plurality of second primary particles with a particle diameter of 100 nm or less containing the metal oxide and the addition element. At least a part of the first and second primary particles has a surface thickening area where a content ratio of the addition element is locally enhanced at the surface layer part. COPYRIGHT : (C)2006, JPO&NCIPI