Catalytic Converter: Description and Operation

Exhaust System:

SYSTEM OPERATION

Two three way catalytic converters are used to reduce CO, HC, and NOx emissions. For efficient operation, the front converter is placed close to the exhaust manifold so that it will heat up quickly and purify the exhaust gas efficiently when the engine is running at idle. The front converter also protects the main converter from damage by acting as a phosphorus and lead filter. The catalytic converters reduce CO and HC emissions through oxidation, and NOx emissions by chemical reaction. The active material in the converters are platinum and rhodium. The volume of the front converter is 400 cc (24.4 ci), and the volume of the rear converter is 2900 cc (176.9 ci).
If the fuel system maintains an optimum air fuel ratio, with oxidation of CO content and HC, the catalytic converter reduces the emission of NOx. The exhaust emitted by the car to the atmosphere consists mainly of CO2, H2O, and pure nitrogen.