What Materials are Used in Catalytic Converters?

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A catalytic converter is a vehicle emissions control device that is used to convert toxic byproducts of combustion (occurring in the exhaust of an internal combustion engine) to less toxic substances by performing catalyzed chemical reactions. The reactions tend to vary depending on the type of catalyst installed. What materials are used in catalytic converters? News About Intumescent Mats

What Materials are Used in Catalytic Converters?

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This vehicle emission control device was invented by Eugene Houdry, a French mechanical engineer involved with catalytic oil refining. In 1973, former General Motors President Robert Stempel decided to begin their implementation in automobiles.

Since then, many scientists have been working on the development of the catalytic converter and as of 2010, they are mandatory on all cars in the US.

Although these devices are primarily used in exhaust systems in automobiles, they are also modified and used on trucks, buses, forklifts, mining equipment, generator sets, locomotives, motorcycles, airplanes, and other engine-fitted devices. They are also used on some wood stoves to control emissions.

The catalytic converter is made up of several materials. The catalyst core or substrate varies according to the vehicle. For example, when these devices are used in automobiles, the core is usually a ceramic monolith with a honeycomb structure.

When manufactured in large quantities, ceramic cores can be inexpensive. Metallic foil monoliths are made of an iron-chromium-aluminum combination and are used in some applications. Metallic cores are less expensive when manufactured for use in small production runs, such as in sportscars in which low back pressure and reliability under constant high load are essential. Both these materials are designed to provide a high surface area to support the catalyst washcoat.

The catalyst washcoat is a carrier for the catalytic converter materials, which is used to disperse the materials over a high surface area. Titanium dioxide, aluminum oxide, silicon dioxide, or a combination of silica and alumina can be used. The catalytic materials are suspended in the washcoat before application to the core. Washcoat materials have rough, irregular surfaces to increase surface area, which helps to maximize the catalytically active surface available to react with the engine exhaust.

The catalyst used in the converter is mostly a precious metal such as platinum, palladium, and rhodium. Platinum is used as a reduction catalyst and as an oxidation catalyst. Although platinum is a very active catalyst and widely used, it is very expensive and not suitable for all applications. Rhodium is used as a reduction catalyst, while palladium is used as an oxidation catalyst.

In some cases, cerium, iron, manganese, and nickel are also used. However, some companies forbid the use of some of these.

The key types of catalytic converters are listed below with a brief introduction:

The catalytic converter was specifically invented to decrease harmful pollution caused by gases produced from the combustion of hydrocarbon-based fossil fuels in cars. Studies reveal that these devices can decrease hydrocarbon emissions by about almost 87%, carbon monoxide by 85%, and nitrous oxide by 62% during the expected life of a vehicle.

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Gary graduated from the University of Manchester with a first-class honours degree in Geochemistry and a Masters in Earth Sciences. After working in the Australian mining industry, Gary decided to hang up his geology boots and turn his hand to writing. When he isn't developing topical and informative content, Gary can usually be found playing his beloved guitar, or watching Aston Villa FC snatch defeat from the jaws of victory.

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I need a catalytic converter that is aflame and which I can reroute the gases produced from it's burning, to fuel my vehicle. Like a Worm.

Hi, what are the advantages in use of talc in the composition of automotive catalysts?

yes I no beads are not used any more , but is it true they used 90% more palladium back then because no one new much about palladium back then and cheaper.

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What Materials are Used in Catalytic Converters?

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