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Catalytic Converters

( Article Type: Explanation )

Certain metals have the property to act as catalysts. This is a characteristic, that enables them to promote, speed up or make more efficient, certain chemical reactions without being permanently changed themselves. The platinum group of metals can convert or ‘catalyse’ the breakdown of noxious exhaust gases of petrol driven cars (nitrogen oxides, carbon monoxide and hydrocarbons) to safer nitrogen, carbon dioxide and water.

A catalytic converter, or auto catalyst, fitted correctly to a car’s exhaust system, can reduce the effect of the noxious gases on the environment. However, auto catalysts will only work if the car uses unleaded petrol. This is one of the reasons unleaded petrol is being introduced in South Africa.

A growing concern regarding the effects of vehicle exhaust emissions on human health and natural ecosystems is causing serious consideration to be given to requiring all new vehicles to have catalytic converters fitted. If this were to be introduced, its effects would be gradual whilst the existing stock of vehicles without converters came to the end of their lives. This could take between 10 and 25 years to complete.