Abstract: 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.

Abstract: A device is described which provides thermally durable NO2 generation in conjunction with efficient heat-up performance for filter regeneration, and low temperature HC (hydrocarbon) and CO activity. Importantly, it provides both functions while minimizing PGM (platinum group metals) utilization and its associated impact on catalyst cost.

Abstract: A device and process for storing hydrocarbons as part of an exhaust emission control system and diagnosing the state of said device based on the incorporation of reactive metal species within the porous microstructure of the associated hydrocarbon adsorbent.

Abstract: A device and process for storing hydrocarbons as part of an exhaust emission control system and diagnosing the state of said device based on the incorporation of reactive metal species within the porous microstructure of the associated hydrocarbon adsorbent.

Abstract: In an exhaust aftertreatment system, two LNTs having differing compositions are configured in series downstream from an inline fuel reformer. The downstream LNT is adapted for desulfation at higher temperatures than the upstream LNT. During desulfation, the system develops temperature gradients with the temperatures increasing in the direction of exhaust flow. The ordering of the LNTs is designed utilize these gradients. In a preferred embodiment, the system also includes two SCR catalysts having different compositions. The SCR catalyst with a composition adapted to tolerate higher temperatures is located nearer the downstream end of the system.

Abstract: A device is described which provides thermally durable NO2 generation in conjunction with efficient heat-up performance for filter regeneration, and low temperature HC (hydrocarbon) and CO activity. Importantly, it provides both functions while minimizing PGM (platinum group metals) utilization and its associated impact on catalyst cost.

Abstract: A method of reducing NOx in a vehicle exhaust operating by alternating exhaust flow between two lean NOx traps and directing the emerging exhaust to a downstream SCR catalyst system. While exhaust predominantly flows through one of the lean NOx traps, a reductant is provided to the other NOx trap so as to produce ammonia that is also directed to the SCR catalyst system. An exhaust system implementing the method of the invention is also provided.

Abstract: 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.

Abstract: In an exhaust aftertreatment system, two LNTs having differing compositions are configured in series downstream from an inline fuel reformer. The downstream LNT is adapted for desulfation at higher temperatures than the upstream LNT. During desulfation, the system develops temperature gradients with the temperatures increasing in the direction of exhaust flow. The ordering of the LNTs is designed utilize these gradients. In a preferred embodiment, the system also includes two SCR catalysts having different compositions. The SCR catalyst with a composition adapted to tolerate higher temperatures is located nearer the downstream end of the system.