Processo para reduzir no2 em sistema de exaustão de combustão

摘要

An exhaust system for treating an exhaust gas composition having NO2 in a first NO2 concentration. The exhaust system includes a first catalyst that contacts a first portion of the exhaust gas composition converting it into a first oxidized exhaust mixture that includes NO2 in a second NO2 concentration that is greater than the first NO2 concentration. The system further includes a bypass that receives a second portion of the exhaust gas composition and a recombination section positioned downstream of the first catalyst. The first oxidized exhaust mixture is combined with the second portion of the exhaust gas composition to produce a first combined exhaust gas mixture. A second catalyst converts the first combined exhaust gas mixture to a second combined exhaust gas mixture having a third NO2 concentration that is less than the second NO2 concentration. The method used by the exhaust system is also provided.