Carbon Monoxide
Remove harmful pollutants from the exhaust gases.
Catalytic Converters
Catalytic Converters
A catalytic converter is used to remove toxic gases from the exhaust.
Nitrogen and carbon dioxide.
So the gases are in contact with a bigger area of catalyst
A catalytic converter is a piece of an automotive exhaust system. The catalytic converter often contains precious metals. As exhaust gases pass through the catalytic converter, chemical reactions occur which convert pollutant gases into less harmful ones.
Catalytic Converters operate their best at high temperatures. Cooling the gasses would be counter productive.
Because it converts toxic gases from the exhaust into less toxic substances. It does this by means of a catalyst which stimulaters a chemical reaction which changes the toxic gases. Therefore the term Catalytic Converter.
because they do not help to reduce the amount of co2 in the atmosphere
You are probably referring to catalytic converters. These are mechanisms that turn harmful gases and other particles into nitrogen gas. The correct spelling will lead to you a variety of helpful websites.
Catalytic converters contain something called platinum or rhodium or palladium flakes. Here is a quote from the Related Link: "Catalytic converter -- an integral part of vehicle emission control systems since 1975. Oxidizing converters remove hydrocarbons and carbon monoxide (CO) from exhaust gases, while reducing converters control nitrogen oxide (NOx) emissions. Both use noble metal (platinum, palladium or rhodium) catalysts that can be 'poisoned' by lead compounds in the fuel or lubricant."