Catalytic converter is a device, fitted onto the exhaust pipes of petrol-driven automobiles which help reduce the emission of environmentally damaging gases from the automobiles. The exhaust fumes of petrol-driven automobiles using unleaded petrol contain gases like the nitrogen oxides, carbon monoxide and benzene which are harmful to health when inhaled. The catalytic converter helps convert these gases into harmless carbon dioxide, steam and nitrogen. The converter is made up of grids of ceramics or metal coated with catalysts like platinum, vanadium or rhodium. When the exhaust gases pass over it, the catalyst brings about chemical reactions converting the harmful gases into harmless ones. The converter cannot be used in automobiles using leaded petrol because the lead which is used in the fuel as an anti-knocking agent can inactivate the catalyst and render the device useless.
