Federal
Three-way Catalyst System And Operations:
PURPOSE
The three way catalyst (TWC) reduces oxides of nitrogen (NOx) as well as HC and CO, producing nitrogen, water, and carbon dioxide as by-products.
OPERATION
The catalytic converter consists of an aluminum carrier coated with a catalyst (active material) such as platinum or palladium which is enclosed in a heat resistant steel shell. The catalyst material uses residual oxygen in the exhaust gasses to convert HC, CO, and in some cases NOx, into less harmful substances.