Refractory oxides based silver-tungsten lean-NOx catalyst

摘要

This invention is a catalyst for treating the exhaust gases produced during lean-burn engine operation, the gases comprising nitrogen oxides, carbon monoxide and hydrocarbons. The catalyst comprises a support material comprising gamma-alumina, a layer of about 0.01 to 1.5 wt. % tungsten deposited onto the support followed by a layer of about 1 to 3 wt. % silver, both being individually based on the weight of the support material.