Patent ID: 7696126

Claim:
A method of producing an oxidation catalyst for cleaning exhaust gas comprising a composite oxide containing a first metal element A and a second metal element B and represented by the general formula of ABO 3 , comprising the steps of: selecting the first metal element A and the second metal element B such that the ratio of the ionic radius of the first metal element A to the ionic radius of the second metal element B is in the range of from 1.349 to 1.580, grind mixing acetate, nitrate or oxide of the first metal element A, acetate or nitrate of the second metal element B, and urea to form a grind mixed material, reacting the grind mixed material to form reactant material, and grind mixing the reactant material and subsequently firing the reactant material at 600 to 1200° C. for 1 to 5 hours.