Patent attributes
A layered three-way conversion catalyst having the capability of simultaneously catalyzing the oxidation of hydrocarbons and carbon monoxide and the reduction of nitrogen oxides is disclosed. Engine exhaust treatment system and methods of using the same are also provided. The catalytic material can be provided in layers such that a larger amount of oxygen storage component is provided in a downstream zone as compared to an upstream zone. For example, the upstream zone can be configured to have one, two, or three layers, and the downstream zone can be independently configured to have one, two, or three layers. In one or more embodiments, the catalyst supported on a carrier has three layers, where at least two of the layers are zoned to have an oxygen storage component being present in an upstream zone in an amount that is less than the oxygen storage component present in the downstream zone.
