Exhaust gas control apparatus for internal combustion engine

摘要

An Ag catalyst (32) is provided in an exhaust passage (14) of an internal combustion engine (10). Also, a three way catalyst (34) or a PM filter (62) is provided downstream of the Ag catalyst (32), and an ozone generator (36) is provided upstream of the Ag catalyst (32). During a cold start, for example, ozone is supplied to the Ag catalyst (32). This ozone reacts with the Ag catalyst (32) and as a result, purifies CO in the exhaust gas. Accordingly, CO in the exhaust gas can start to be purified at a low temperature.