Abstract: A system for filtering and oxidizing particulate matter produced by a gasoline direct injection engine is disclosed. In one embodiment, engine cylinder air-fuel is adjusted to allow soot to oxidize at an upstream particulate filter while exhaust gases are efficiently processed in a downstream catalyst.

Abstract: A low-temperature catalyst is provided for reducing cold-start hydrocarbon emissions. The catalyst comprises a platinum group metal impregnated onto an oxygen storage material. The catalyst may be used alone or may be included in a hydrocarbon trap containing a hydrocarbon adsorption material therein. The catalyst/hydrocarbon trap is positioned in the exhaust system of a vehicle downstream from a close-coupled catalyst such that the exhaust temperature at the catalyst location does not exceed 850° C. during normal vehicle operation and when combined with a hydrocarbon adsorption material in a trap, the exhaust temperature does not exceed 700° C.

Abstract: A system for filtering and oxidizing particulate matter produced by a gasoline direct injection engine is disclosed. In one embodiment, engine cylinder air-fuel is adjusted to allow soot to oxidize at an upstream particulate filter while exhaust gases are efficiently processed in a downstream catalyst.

Abstract: Embodiments are described to improve the durability of a lean NOx aftertreatment system. According to one embodiment of the present invention an air injection system is used to inject air continuously into the exhaust system between the upstream three-way catalyst and the downstream selective catalytic reduction (SCR) catalyst when the engine is operating at stoichiometric or rich air/fuel ratios and the exhaust temperatures are above a calibratable level (e.g., 700° C.). In another embodiment, an oxidation catalyst is positioned downstream of the air injection point to prevent exothermic reactions from occurring on the SCR. In another embodiment, the reductant for the SCR is generated in-situ. In yet another embodiment, a diverter valve with a reduction catalyst in a bypass arm is utilized to bypass the SCR during high load conditions.

Abstract: A low-temperature catalyst is provided for reducing cold-start hydrocarbon emissions. The catalyst comprises a platinum group metal impregnated onto an oxygen storage material. The catalyst may be used alone or may be included in a hydrocarbon trap containing a hydrocarbon adsorption material therein. The catalyst/hydrocarbon trap is positioned in the exhaust system of a vehicle downstream from a close-coupled catalyst such that the exhaust temperature at the catalyst location does not exceed 850° C. during normal vehicle operation and when combined with a hydrocarbon adsorption material in a trap, the exhaust temperature does not exceed 700° C.

Abstract: A system for filtering and oxidizing particulate matter produced by a gasoline direct injection engine is disclosed. In one embodiment, engine cylinder air-fuel is adjusted to allow soot to oxidize at an upstream particulate filter while exhaust gases are efficiently processed in a downstream catalyst.

Abstract: A system for filtering and oxidizing particulate matter produced by a gasoline direct injection engine is disclosed. In one embodiment, engine cylinder air-fuel is adjusted to allow soot to oxidize at an upstream particulate filter while exhaust gases are efficiently processed in a downstream catalyst.

Abstract: Embodiments are described to improve the durability of a lean NOx aftertreatment system. According to one embodiment of the present invention an air injection system is used to inject air continuously into the exhaust system between the upstream three-way catalyst and the downstream selective catalytic reduction (SCR) catalyst when the engine is operating at stoichiometric or rich air/fuel ratios and the exhaust temperatures are above a calibratable level (e.g., 700° C.). In another embodiment, an oxidation catalyst is positioned downstream of the air injection point to prevent exothermic reactions from occurring on the SCR. In another embodiment, the reductant for the SCR is generated in-situ. In yet another embodiment, a diverter valve with a reduction catalyst in a bypass arm is utilized to bypass the SCR during high load conditions.

Abstract: Embodiments are described to improve the durability of a lean NOx aftertreatment system. According to one embodiment of the present invention an air injection system is used to inject air continuously into the exhaust system between the upstream three-way catalyst and the downstream selective catalytic reduction (SCR) catalyst when the engine is operating at stoichiometric or rich air/fuel ratios and the exhaust temperatures are above a calibratible level (e.g., 700° C.). In another embodiment, an oxidation catalyst is positioned downstream of the air injection point to prevent exothermic reactions from occurring on the SCR. In another embodiment, the reductant for the SCR is generated in-situ. In yet another embodiment, a diverter valve with a reduction catalyst in a bypass arm is utilized to bypass the SCR during high load conditions.

Abstract: The reduction of a NOx trap upon engine shutdown is disclosed. One disclosed embodiment comprises adjusting a timing of creating a reductive environment in the exhaust conduit upstream of the lean NOx trap based upon the determined engine stop position. The creation of a reductive environment in the exhaust conduit upstream of the lean NOx trap may help to at least partially reactivate the lean NOx trap during engine shutoff.

Abstract: A method for operating an engine with a fuel reformer is presented. In one embodiment a method for operating an engine by injecting a gaseous fuel and a liquid fuel to at least an engine cylinder is presented. The method may prioritize the injection of the gaseous fuel in response to an amount of gaseous fuel stored in a fuel storage tank.

Abstract: Various systems and methods are described for a controlling a flow of reformate fuel in a fuel system which includes a reformer and a storage tank coupled to an engine in a vehicle. The system includes a pump located between the reformer and the storage tank that is selectively operated in order to reduce parasitic losses on the system.

Abstract: A method for operating an engine with a fuel reformer is presented. In one embodiment a method for operating an engine by injecting a gaseous fuel and a liquid fuel to at least an engine cylinder is presented. The method may prioritize the injection of the gaseous fuel in response to an amount of gaseous fuel stored in a fuel storage tank.

Abstract: A system for filtering and oxidizing particulate matter produced by a gasoline direct injection engine is disclosed. In one embodiment, engine cylinder air-fuel is adjusted to allow soot to oxidize at an upstream particulate filter while exhaust gases are efficiently processed in a downstream catalyst.

Abstract: A method for operating an engine with a fuel reformer is presented. In one embodiment a method for operating an engine by injecting a gaseous fuel and a liquid fuel to at least an engine cylinder is presented. The method may prioritize the injection of the gaseous fuel in response to an amount of gaseous fuel stored in a fuel storage tank.

Abstract: The reduction of a NOx trap upon engine shutdown is disclosed. One disclosed embodiment comprises adjusting a timing of creating a reductive environment in the exhaust conduit upstream of the lean NOx trap based upon the determined engine stop position. The creation of a reductive environment in the exhaust conduit upstream of the lean NOx trap may help to at least partially reactivate the lean NOx trap during engine shutoff.

Abstract: The reduction of a NOx trap upon engine shutdown is disclosed. One disclosed embodiment comprises adjusting a timing of creating a reductive environment in the exhaust conduit upstream of the lean NOx trap based upon the determined engine stop position. The creation of a reductive environment in the exhaust conduit upstream of the lean NOx trap may help to at least partially reactivate the lean NOx trap during engine shutoff.

Abstract: A diesel exhaust aftertreatment system and method are provided. The system includes a lean NOx trap for reducing NOx and a transition metal-exchanged zeolite booster catalyst positioned downstream from the lean NOx trap for further reducing NOx. The lean NOx trap includes a NOx adsorbent material and one or more platinum group metals, and has a platinum group metal loading of less than about 90 g/ft3. The aftertreatment system provides high NOx conversion over a broad temperature range without the use of ammonia as a major reductant.

Abstract: Various systems and methods are described for a controlling a flow of reformate fuel in a fuel system which includes a reformer and a storage tank coupled to an engine in a vehicle. The system includes a pump located between the reformer and the storage tank that is selectively operated in order to reduce parasitic losses on the system.

Abstract: Various systems and methods are described for a controlling a flow of reformate fuel in a fuel system which includes a reformer and a storage tank coupled to an engine in a vehicle. The system includes a pump located between the reformer and the storage tank that is selectively operated in order to reduce parasitic losses on the system.