METHOD AND DEVICE FOR REDUCING THE NO2 EMISSION OF THE INTERNAL COMBUSTION ENGINE WITH COMPRESSION Ignition, WORKING ON POOR MIXTURES

摘要

1. A method of reducing the NO2 emission of a compression ignition internal combustion engine operating in lean mixtures, where the exhaust gas of an engine containing NO2 is brought into contact with a catalyst active in the reduction of NO2 to NO and containing at least one platinum group metal when provided that the platinum metal is not platinum, and at least one metal oxide is active in oxidation-reduction reactions, and thereby reducing the NO2 contained in the exhaust gas to NO by reaction with CO, hydrocarbons and / or soot, risutstvuyuschey in the exhaust gas. ! 2. The method according to claim 1, where at least one metal of the platinum group is palladium. ! 3. The method according to claim 1, where at least one metal oxide active in redox reactions is selected from the group consisting of MnO2, Fe2O3, SnO2, PrO2 and CeO2. ! 4. The method according to claim 1, where at least one metal oxide active in the oxidation-reduction reactions is stabilized by one or more oxides selected from the group consisting of TiO2, WO3, SiO2, HfO2, ZrO2, MgO, CaO Al2O3, La2O3 and BaO. ! 5. The method according to claim 1, wherein the catalyst consists of Pd and CeO2 stabilized by ZrO2. ! 6. The method according to any one of claims 1 to 5, where the catalyst is deposited on or located inside the wall of the particulate filter. ! 7. A device for reducing the emission of NO2 of a compression ignition internal combustion engine operating on lean mixtures, comprising an engine exhaust gas system provided with a catalyst that is effective in the reaction of converting NO2 with CO, HC and / or carbon black to NO, where the catalyst contains at least one platinum group metal, provided that the platinum metal is not platinum, and, p