EXHAUST EMISSION CONTROL SYSTEM FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide an exhaust emission control system for an internal combustion engine capable of obtaining a comparatively high exhaust gas purification rate immediately after the internal combustion engine is started using an inexpensive three-way catalyst. SOLUTION: This exhaust emission control system 1 is provided with a purifier 4 arranged in an exhaust pipe 3 of the internal combustion engine 2 and having the three-way catalyst and a catalyst temperature rise controller 5 increasing a temperature of the three-way catalyst to activate the three-way catalyst in accordance with the start of the internal combustion engine 2. A catalyst having perovskite double oxide containing a lanthanoid mixture extracted from bastnaesite is used as the three-way catalyst. The catalyst temperature rise controller 5 increases an amount of air to be sucked into the internal combustion engine 2 and delays an ignition time.