PREPARATION METHOD OF DIESEL OXIDATION CATALYST

摘要

PROBLEM TO BE SOLVED: To provide a preparation method of a high-performance diesel oxidation catalyst having a function for oxidizing nitrogen monoxide included in exhaust gas having the atmosphere containing oxygen excessively into nitrogen dioxide, and a function for accelerating combustion of an unburned fuel in the exhaust gas, incomplete combustion products or the like.SOLUTION: In a preparation method of a diesel oxidation catalyst in which a platinum group metal is carried on an oxide carrier, when carrying on the oxide carrier by using a solution containing the platinum group metal compound, an oil-soluble carboxylic acid having a carbon number of 3 or larger is allowed to coexist, and then burned.