Catalytic Converter

Three Way Catalytic Converter
The three way catalytic (TWC) converter contains either platinum (Pt) and rhodium (Rh) or palladium (Pd) and rhodium (Rh). The TWC converter catalyzes the oxidation reactions of unburned HCs and CO and the reduction reaction of NOx. The three-way conversion can be best accomplished by always operating the engine air fuel/ratio at or close to stoichiometry.