EXHAUST GAS PURIFICATION CATALYST AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method of an exhaust gas purification catalyst, which can prevent abnormal overheating at calcination, and can obtain the catalyst having high-level catalyst activity in which ultra-fine particles containing mercury are stably held.SOLUTION: A manufacturing method of an exhaust gas purification catalyst having a metal oxide carrier and ultra-fine particles which are held at the metal oxide carrier and contain mercury includes: a step of obtaining a silver-based choroid solution in which choroid particles containing mercury are dispersed by independently and directly introducing a first raw material solution containing mercury ions and a second raw material solution containing water-soluble amine into a region in which a shearing speed reaches 1,000 to 50,000 secand mixing them in equal quality; and a step of obtaining the exhaust gas purification catalyst by calcining the silver-based choroid solution in air after making it contact with the metal oxide carrier. The method is also characterized in that an average particle diameter of the choroid particles is within a range of 1.0 to 3.5 nm.