COMPOUND OXIDE AND METHOD FOR PRODUCING THE SAME, AND AUXILIARY CATALYST FOR CLEANING FLUE GAS

摘要

PROBLEM TO BE SOLVED: To provide an auxiliary catalyst for cleaning flue gas having both a high specific surface area and high oxygen occlusion and release capability. SOLUTION: This compound oxide to be used as a carrier comprises CeO2 , ZrO2 and a metal oxide which does not react with CeO2 nor with ZrO2 , which contains a pyrochlore phase where Ce and Zr are regularly disposed. As CeO2 -ZrO2 compound oxide and the metal oxide which does not react with CeO2 nor with ZrO2 act as a barrier against each other, grain growth due to high heat at the reduction treatment for forming the pyrochlore phase is suppressed, and oxygen occlusion and release capability is enhanced by the formation of the pyrochlore phase.