Denitration catalyst composition and method of denitration using same

Abstract

A denitration catalyst composition to efficiently and reductively remove nitrogen oxides from exhaust gas of a boiler or an internal combustion engine operated in lean-combustion, such as a gasoline engine, a diesel engine, by carbon monoxide and hydrocarbons; and a denitration method using the catalyst composition. In the denitration catalyst composition, a precious metal element having Rh as an essential component is supported on a zirconium oxide-based carrier formed by condensing or mixing primary particles having a zirconium oxide as a main component, and further a cerium-containing oxide (B) is present at the surface of the zirconium oxide-based carrier and at the gap of the secondary particles; and a denitration method characterized in that exhaust gas containing NO, CO and O2 is contacted with the denitration catalyst composition, under oxidative atmosphere having an air/fuel ratio of 14.7 or higher, at a temperature of 400 to 800° C.

Dependencies are inferred from the claim text.