Close-coupled catalyst for purifying exhaust gas and process for making the same

摘要

Exhaust gas purification catalyst consists of barium oxide and palladium deposited together on an aluminum oxide carrier material. The average particle size of the palladium crystals on the carrier material is 3-7 nm. An Independent claim is also included for a process for the production of an exhaust gas purification catalyst comprising: (1) suspending aluminum oxide and barium hydroxide in water so that the barium hydroxide goes into solution and the pH of the suspension shifts into the base region; (2) introducing an aqueous solution of a precursor of palladium to the suspension with constant stirring using capillary injection; (3) coating a honeycomb body with the resulting suspension; and (4) drying and calcining.