Patent ID: 6245307
Filing Date: 2001-06-12
Classification: B01D,B01J,F02B,Y02A,Y02T

Abstract:
A method for the purification of the exhaust gas from an automobile carrying a lean burn engine using gasoline as a fuel thereof, said lean burn engine being used at an air/fuel (A/F) ratio of not less than 15 at least during travel at a constant rate, which comprises:causing said exhaust gas from said automobile to contact a catalyst having deposited on an inert carrier a mixture of a catalytically active component consisting essentially of palladium, an oxide of at least one alkali metal selected from the group consisting of potassium, sodium, rubidium, and cesium, and an oxide of at least one iron family metal selected from the group consisting of cobalt, nickel, and iron with a refractory inorganic oxide and subsequently;causing said exhaust gas to contact an oxidizing catalyst or a three-way catalyst.