Toxic components of the fulfilled gases are hydrocarbons (not burned down fuel), carbon monoxide and an oxide of nitrogen. For transformation of these connections in nontoxical the three-component catalytic converter established in system of release at once behind a reception pipe of mufflers serves.

Fig. 10-12. Converter: 1 — the ceramic block with catalysts

In converter (fig. 10-12) there are ceramic elements with microchannels on which surfaces catalysts are applied: two oxidizing and one recovery. Oxidizing catalysts (platinum and palladium) promote transformation of hydrocarbons to water vapor, and carbon monoxide — in harmless carbon dioxide. The recovery catalyst (rhodium) accelerates chemical reaction of restoration of nitrogen oxides and their transformation into harmless nitrogen.
It is necessary for effective neutralization of toxic components and the fullest combustion of air-fuel mix that 1 part of fuel fell on 14,6–14,7 parts of air.
Such accuracy of dispensing is provided with electronic system of injection of fuel which continuously corrects supply of fuel depending on operating conditions of the engine and a signal from the sensor of concentration of oxygen in the fulfilled gases.

Operation of the engine with converter on ethylated gasoline is not allowed. It will lead to bystry failure of converter and the sensor of concentration of oxygen.