Abstract: The invention provides devices and methods for generating H2 and CO in an O2 containing gas stream. The invention also provides devices and methods for removal of NOX from an O2 containing gas stream, particularly the oxygen-rich exhaust stream from a lean-burning engine, such as a diesel engine. The invention includes a fuel processor that efficiently converts added hydrocarbon fuel to a reducing mixture of H2 and CO. The added fuel may be a portion of the onboard fuel on a vehicle. The H2 and CO are incorporated into the exhaust stream and reacted over a selective lean NOX catalyst to convert NOX to N2. thereby providing an efficient means of NOX emission control.

Abstract: The present invention provides systems and methods to improve the performance and emission control of internal combustion engines equipped with nitrogen oxides storage-reduction (“NSR”) emission control systems. The system generally includes a NSR catalyst, a fuel processor located upstream of the NSR catalyst, and at least one fuel injection port. The fuel processor converts a fuel into a reducing gas mixture comprising CO and H2. The reducing gas mixture is then fed into the NSR catalyst, where it regenerates the NSR adsorbent, reduces the NOx to nitrogen, and optionally periodically desulfates the NSR catalyst. The fuel processor generally includes one or more catalysts, which facilitate reactions such as combustion, partial oxidation, and/or reforming and help consume excess oxygen present in an engine exhaust stream. The methods of the present invention provide for NSR catalyst adsorbent regeneration using pulsed fuel flow. Control strategies are also provided.

Abstract: The present invention provides systems and methods to improve the performance and emission control of internal combustion engines equipped with nitrogen oxides storage-reduction (“NSR”) emission control systems. The system generally includes a NSR catalyst, a fuel processor located upstream of the NSR catalyst, and at least one fuel injection port. The fuel processor converts a fuel into a reducing gas mixture comprising CO and H2. The reducing gas mixture is then fed into the NSR catalyst, where it regenerates the NSR adsorbent, reduces the NOx to nitrogen, and optionally periodically desulfates the NSR catalyst. The fuel processor generally includes one or more catalysts, which facilitate reactions such as combustion, partial oxidation, and/or reforming and help consume excess oxygen present in an engine exhaust stream. The methods of the present invention provide for NSR catalyst adsorbent regeneration using pulsed fuel flow. Control strategies are also provided.

Abstract: An exhaust aftertreatment system is provided with a large channel combustor, a fuel reformer, and a lean NOX trap. The lean NOX trap is denitrated by steps comprising: heating the fuel reformer to steam reforming temperatures by introducing vaporized fuel to the large channel combustor and combusting a portion of the vaporized fuel under lean conditions, then making the exhaust-injected fuel mixture overall rich, whereby the fuel reformer produces syn gas that denitrates the lean NOX trap. The fuel reformer has a low thermal mass, whereby it is designed to heat to at least about 500° C. and catalyze steam reforming reaction with each denitration. The large channel combustor is a monolith having an average channel size larger than the fuel reformer and a thermal mass no more than about 20% that of the fuel reformer, whereby the large channel combustor facilitates low temperature startup of the fuel reformer.

Abstract: Described here are systems and methods for treating fuel injected exhaust streams. In general, the systems comprise a fuel injector, a pre-combustor, and a fuel combustor. The methods described herein include methods for regenerating a NOx trap or a DPF, and methods for generating a substantially uniform fuel air mixture at a fuel combustor inlet, or a substantially uniform temperature at a fuel combustor outlet. The methods of regenerating a NOx trap typically comprise the steps of injecting fuel into an exhaust stream, passing the stream through a pre-combustor, operating the pre-combustor to at least partially combust the injected fuel, reacting the fuel and exhaust stream mixture within a fuel combustor to generate a reducing gas mixture, and introducing the reducing gas mixture into a NOx trap, whereby the NOx trap is regenerated. Similar methods for regenerating a diesel particulate filter are also described. Control strategies are also provided.