Catalytic Converter

The pollutants (carbon monoxide, hydrocarbons and nitrogen oxides) produced by the motor combustion are converted into harmless gases by using a catalytic converter. Typical catalysts are the precious metals platinum, palladium and rhodium that are coated on mostly ceramic combs using the so-called "washcoats". The larger the surface of the combs is, the better the cleaning effect is. The coated substrate is embedded in metallic housings with the help of fiber mats (canning).



Three-Way Catalyst (TWC):
For passenger cars with gasoline engines, we use three-way catalytic converters that can simultaneously convert all three pollutants in a stoichiometric fuel / air mixture (Lambda = 1) by more than 99%.


Diesel Oxidation Catalyst (DOC):
For passenger cars with diesel engines, we use diesel oxidation catalytic converters (DOC), usually in connection with a diesel particle filter (DPF). As catalyst, we use mostly platinum or a combination of platinum and palladium.


To meet future NOx limits (Euro 5 and 6), additional DeNox systems are needed depending on vehicle weight, including either SCR catalysts or lean nox traps (LNT).