FIELD: mechanical engineering, internal combustion engines. SUBSTANCE: invention can be used to control conversion of exhaust gases of internal combustion engines. Proposed device contains catalyst-accumulator of nitrogen oxides, activity range ΔTNOx for accumulation of nitrogen oxides at excess air coefficient in exhaust gases higher than 1, and releasing nitrogen oxides at excess air coefficient lower than or equal to 1, and sulfur trap arranged in direction of flow before nitrogen catalyst-accumulator having desulfurization temperature ΔTNOx higher than which surfaces accumulated on trap decompose at excess air coefficient lower than or equal to 1. nitrogen oxides from exhaust gases are accumulated on catalyst-accumulator, and sulfur oxides, on sulfur trap at excess air coefficient great than 1 and temperatures Tc of exhaust gases within activity range ΔTNOx, and temperature before sulfur trap lower than its desulfurization temperature TS,DeSOx. Owing to cyclic reduction of excess air coefficient for exhaust gases to value lower than 1, nitrogen oxides accumulated on catalyst-accumulator are released (end of cycle of accumulation). Desulfurization of trap takes place expiration of preset number of cycles N1 of nitrogen oxides accumulation. This is provided by raising temperature of exhaust gases before sulfur trap to value higher than its desulfurization temperature TS,DeSOx and by decreasing excess air coefficient in exhaust gases to value lower than 1. EFFECT: improved efficiency. 21 cl, 21 dwg
