EXHAUST GAS PURIFICATION CATALYST

摘要

This invention relates to a three-way catalyst for use in the purification of exhaust gas from an internal combustion engine, a method of making the same and an exhaust system including a three-way catalyst for an internal combustion engine. Specifically, the three-way catalyst comprises a substrate suitable for the purification of exhaust gas from an internal combustion engine wherein the catalyst comprises a substrate, a refractory oxide layer, tungsten and/or one or more tungsten containing compounds and one or more platinum group metals. The catalyst produces food suppression of ammonia production in oxygen lean exhausts.