초록 ▼

A catalyst for the purification of an exhaust gas emitting from a lean burn engine using gasoline as a fuel thereof and a method for the purification are provided. The catalyst has deposited on an inert carrier a mixture of a catalytically active component comprising palladium, an oxide of at least

A catalyst for the purification of an exhaust gas emitting from a lean burn engine using gasoline as a fuel thereof and a method for the purification are provided. The catalyst has deposited on an inert carrier a mixture of a catalytically active component comprising 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. This catalyst is used either alone or in combination with an oxidizing catalyst or a three-way catalyst for the purification of the exhaust gas from the lean burn engine using gasoline as a fuel thereof.

대표청구항 ▼

[ What is claimed is:] [1.]1. 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:c

[ What is claimed is:] [1.]1. 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.