Catalytic Converter

A catalytic converter is a device in the Exhaust System of an automotive engine that converts environmentally harmful exhaust gases into harmless gases by promoting a chemical reaction between a catalyst and pollutants. The catalytic converter decreases the emission of hydrocarbons, carbon monoxide, nitrogen oxide, or of all three.

In the most common type of catalytic converter, the exhaust gases are passes through a bed, or honeycomb, of small beads coated with the catalysts platinum and palladium. The catalyst in the nitrogen oxide converter splits the nitrogen from the oxygen so that nitrogen gas, carbon dioxide, and water are formed. In an automobile equipped with a catalytic converter, lead-free gasoline must be used in order to prevent coating the catalyst with lead. 

One type of automobile catalytic converter consists of a porous, heat-resistant, inert material coated with a catalyst. It is supported by a wire screen and enclosed by a metal shell. The end come of the device is connected to an engine's exhaust manifold, and the opposite end is sealed to the muffler. As hydrocarbon (HC), carbon monoxide (CO), and oxigen (O2) in the exhaust gases pass through the system, they are converted into water (H2O) and carbon dioxide (CO2).