Reduction in the quantity of NOx in lean exhaust gas of motor vehicle engines

摘要

A catalyst is described for reducing the quantity of nitrogen oxides in lean exhaust gas of motor vehicle engines. The catalyst contains, on a structure reinforcing body, a first catalytic coating of an aluminum oxide and/or cerium oxide of large surface area impregnated with a mixture of iridium and platinum as catalytically active noble metal components. A second catalytic coating including a zeolite of the mordenite type containing copper and/or iron is applied to the first coating layer.