| 摘要 |
PURPOSE: To carry out conversion with maintaining tertiary activity by using a relatively low amount of rhodium in a multi-stage catalytic system for converting Nox , Co and hydrocarbons into harmless products. CONSTITUTION: A first stage for conversion of the major portion of Nox and a proportion of Co and hydrocarbons into harmless products, and a second stage via a second stage reaction for bringing the discharged mixture from the first stage into contact with a catalyst to convert the remaining Co and hydrocarbons into harmless products, are included. A catalyst in the first step comprises substantially rhodium and a zeolite component, and a catalyst in the second stage comprises noble metal(s) and a carrier. |
