One of the many ways available to curb emission control that is available in the world today is through the catalytic converter. The catalytic converter is one of the most effective and most desirable. The device controls emissions by converting the toxic gases in the exhaust into less harmful pollutants by performing redox reactions through the help of catalysts. These catalytic converters are found to be the most helpful when combined with internal combustion engines employed for the generation of power. The internal combustion engines run on fuels that would include petrol, kerosene and diesel and even lead-burn engines, which produce harmful compounds including those of Sulphur and nitrogen. The catalytic reactions on the exhausts can convert them into emissions that would not have severe impacts on the environment.
These devices are of some varying types. The "two-way" converters that were first made available was employed to react oxygen with the carbon monoxide and unburned hydrocarbons to release carbon dioxide and water. But due to the increasing number of pollutants from combustion engines, the two-way converters were no more deemed to be useful and were replaced by "three-way" converters. The catalytic converter parts in these converters would even reduce the oxides of nitrogen. However, the two-way converters would still find use in the lead-burn engines.
The catalytic converter parts together form the intuitive structure of the device. One of the main constituents is the substrate, also called the catalyst support. The core used for most automotive converters has a honeycomb structure mostly made of ceramic. The Kanthal is also used because of the high heat resistance offered by it. The materials are so designed that there is a large surface area. Another part used in the design is the wash-coat. The wash-coat acts like the carrier medium for the catalytic materials. It helps disperse the materials over a large surface area. It is made of titanium dioxide, aluminum oxide, silicon dioxide and others and has a rough surface to maximize surface area.
The third constituent is the ceria or ceria-zirconia and is made of oxides that would act like oxygen storage promoters. Last, but not the least is the catalyst itself, which may be a mix of various precious metals. Platinum is the most desired and is used widely. But its high cost and unwanted additional reactions often lead to the use of alternative metals like palladium and rhodium.