What is a catalytic converter?
A catalytic converter
is a device used to reduce the toxicity of emissions from an internal
combustion engine. It was first introduce in 1975 to comply with the
tightening Environmental Protection Agency (EPA) regulations on auto
exhaust. The catalytic converter provides an environment where chemical reaction can occur that will change toxic combustion by-products to less toxic ones.
The catalytic converter is an integral part of the exhaust system. There are two types of catalytic converter:
the three-way which refers to the reduction of nitrogen oxides,
oxidation of carbon monoxide, and oxidation of unburnt carcinogenic
hydrocarbons, and the two-way catalytic converter
which has two simultaneous tasks of oxidation of carbon monoxide and
oxidation of the hydrocarbons and was widely used on all engines in the
US until 1981 when the regulation changed to include the control on NOx
emissions. A catalytic converter has several components like the core or
substrate made of ceramic honeycomb whose function is to support the
catalyst, the washcoat, which is a mixture of silicon and aluminum
which is added to the core to give a larger surface area, and lastly,
the catalyst, which is most often made of precious metal. Platinum and
rhodium are used as a reduction catalyst, while platinum and palladium
are used as an oxidization catalyst.
Catalytic converters can suffer from catalyst
poisoning and become ineffective in the presence of lead. Some
conditions like a crack in the valves, oil in the exhaust system or
ignition failure all of which can cause the catalytic converter
to overheat and meltdown.
Catalytic Converter - Discount Catalytic Converters - Catalytic Converters Blog
