Abstract: A method is disclosed of providing a fuel efficient regeneration of an exhaust after-treatment (AT) system that includes a lean oxides of nitrogen (NOX) trap (LNT) and a selective catalytic reduction filter (SCRF) positioned downstream of the LNT. The method includes regulating a selectable position valve. The valve permits a first gas flow portion to pass through the LNT and diverts a remaining second portion of exhaust gas flow from a first passage connecting an engine and the AT system to a second exhaust passage to thereby bypass the LNT. The method also includes regulating a first device to inject fuel into the first portion of the exhaust gas flow. The injection of fuel in to the first portion of the exhaust gas flow provides fuel efficient regeneration of the LNT and promotes NOX conversion and ammonia (NH3) formation in the LNT. A system employing the method is also disclosed.

Abstract: A method for diagnosing an Oxidation Catalyst (OC) device of an exhaust gas treatment system is provided. The method monitors a differential temperature across the OC device. The method determines whether the differential temperature reveals a temperature spike. The method determines that the OC device operates properly in response to determining that the differential temperature reveals a temperature spike.

Abstract: A method for removing NOX from an oxygen-rich exhaust flow produced by a combustion source that is combusting a lean mixture of air and fuel may include passing the oxygen-rich exhaust flow through an exhaust aftertreatment system that includes a NOX oxidation catalyst that includes perovskite oxide particles, a NOX storage catalyst, and a NOX reduction catalyst.

Abstract: A system according to the principles of the present disclosure includes an air/fuel ratio determination module and an emission level determination module. The air/fuel ratio determination module determines an air/fuel ratio based on input from an air/fuel ratio sensor positioned downstream from a three-way catalyst that is positioned upstream from a selective catalytic reduction (SCR) catalyst. The emission level determination module selects one of a predetermined value and an input based on the air/fuel ratio. The input is received from a nitrogen oxide sensor positioned downstream from the three-way catalyst. The emission level determination module determines an ammonia level based on the one of the predetermined value and the input received from the nitrogen oxide sensor.

Abstract: A method for diagnosing an Oxidation Catalyst (OC) device of an exhaust gas treatment system is provided. The method monitors a differential temperature across the OC device. The method determines whether the differential temperature reveals a temperature spike. The method determines that the OC device operates properly in response to determining that the differential temperature reveals a temperature spike.

Abstract: A method of treating an exhaust gas produced by a vehicle internal combustion engine includes conveying the gas through a first reactor including a non-thermal plasma. The gas includes nitric oxide and is transitionable between a first condition in which the gas has a cold-start temperature that is less than or equal to about 150° C., and a second condition in which the gas has an operating temperature that is greater than about 150° C. During the first condition, the method includes contacting the gas and plasma to oxidize the nitric oxide to nitrogen dioxide and form an effluent that includes nitrogen dioxide. The method includes concurrently conveying the effluent through a second reactor including a diesel oxidation catalyst, and storing the nitrogen dioxide within the second reactor during only the first condition. The method includes, after storing, releasing nitrogen dioxide from the second reactor during only the second condition.

Abstract: A palladium-only (i.e., platinum free) oxidation catalyst body is used to oxidize carbon monoxide and hydrocarbons in the exhaust stream of a diesel engine powered vehicle, which is operated at a fuel-lean air-to-fuel ratio (A/F) for much of the time it powers a vehicle. Periodically, a recent history of the temperatures of the exhaust gas at the inlet to the palladium oxidation catalyst body is prepared in a computer control module. And a recent history of the A/F of the operating engine is considered. These temperature and A/F values are then used in determining whether the engine should be temporarily operated in a fuel-rich or stoichiometric A/F mode to provide an exhaust gas composition suitable for rejuvenation of the palladium by reducing its oxide formed during lean operation of the engine.

Abstract: The capacity of a platinum-containing diesel oxidation catalyst (DOC) to simultaneously convert NO to NO2, CO to carbon dioxide, and remaining hydrocarbons to carbon dioxide and water in the exhaust system of a vehicle diesel engine may be evaluated and diagnosed using measured DOC exhaust inlet temperatures and outlet temperatures at a relatively high exhaust temperature and, soon thereafter, at a relatively low exhaust inlet temperature. Values of the platinum-containing DOC exotherms at the high and low DOC inlet temperatures are found to provide a basis for evaluation of both NO conversion and the HC and CO conversion capabilities of the DOC. The process may be repeated as the catalyzed DOC conversion efficiency changes with use. The practice may also be used to evaluate the performance of oxidation catalysts used in a like way in treating the exhaust from a lean-burn gasoline engine.

Abstract: Particles of mixed oxides of cerium, zirconium, and copper (CeZrCuOX) may be prepared as catalysts and used to preferentially catalyze the oxidation of CO in exhaust streams containing CO and NH3. In one practice, this CeZrCuOX catalyst may be used in combination with a close-coupled PGM catalyst which promotes the formation of NH3 in the exhaust during fuel-rich operation, and at least one under-floor NH3-SCR catalyst, which catalyzes the reduction of NOX in the exhaust stream during fuel-lean operation using NH3 as a reductant. During fuel-rich engine operation, the exhaust stream may be doped with oxygen downstream of the PGM catalyst and passed in contact with particles of the CeZrCuOX catalyst so that residual CO in the exhaust may be oxidized to CO2, without oxidation or other conversion of the NH3.

Abstract: A system and method is provided for enhancing the performance of an SCR device, particularly by routinely reducing the amount of reductant deposits accumulated in an exhaust gas system, when the reductant is injected at a reduced temperature. The system may include an engine, an exhaust gas system, an SCR device, an injection device, and a controller configured to execute the present method. The controller may be configured to select an initial injection rate and an initial injection temperature for the reductant; estimate the amount of accumulated reductant deposits present within the exhaust gas system; compare the amount of accumulated reductant deposits to a threshold amount of reductant deposits allowable in the exhaust gas system; and initiate a reductant deposit burn-off mode when the amount of accumulated reductant deposits is greater than the threshold amount of reductant deposits allowable in the exhaust gas system.

Abstract: A method is disclosed of providing a fuel efficient regeneration of an exhaust after-treatment (AT) system that includes a lean oxides of nitrogen (NOX) trap (LNT) and a selective catalytic reduction filter (SCRF) positioned downstream of the LNT. The method includes regulating a selectable position valve. The valve permits a first gas flow portion to pass through the LNT and diverts a remaining second portion of exhaust gas flow from a first passage connecting an engine and the AT system to a second exhaust passage to thereby bypass the LNT. The method also includes regulating a first device to inject fuel into the first portion of the exhaust gas flow. The injection of fuel in to the first portion of the exhaust gas flow provides fuel efficient regeneration of the LNT and promotes NOX conversion and ammonia (NH3) formation in the LNT. A system employing the method is also disclosed.

Abstract: A method of determining aging of a diesel oxidation catalyst (DOC) in an engine exhaust system includes receiving a first sensor signal from a first nitrogen oxides (NOx) sensor positioned in exhaust flow upstream of the DOC. The first sensor signal is indicative of an amount of NOx in the exhaust flow upstream of the DOC. The method further includes receiving a second sensor signal from a second NOx sensor positioned in exhaust flow downstream of the DOC. The second sensor signal is indicative of an amount of NOx downstream of the DOC. A difference between the first sensor signal and the second sensor signal is calculated via a controller. A DOC aging level based on a predetermined correlation between the difference and DOC aging is then determined by the controller.

Abstract: A vehicle includes an internal combustion engine operatively disposed therein. The engine generates exhaust gases. The vehicle further includes an alternator operatively connected to the engine. The alternator produces DC power. An ultracapacitor is operatively connected to the alternator to receive electrical energy therefrom. The vehicle still further includes an exhaust gas treatment system operatively connected to the engine to receive exhaust gases therefrom. The exhaust gas treatment system includes an electrically heated catalyst (EHC) device electrically connected to the ultracapacitor to selectively heat a catalytic exhaust system component. The ultracapacitor stores energy converted by the alternator from vehicle kinetic energy and releases the stored energy to heat the EHC.

Abstract: In one embodiment, a method for controlling nitrogen oxides in an exhaust gas received by an exhaust system, the exhaust system including a first selective catalytic reduction device, an exhaust gas heat recovery device and a second selective catalytic reduction device is provided. The method includes flowing the exhaust gas from an internal combustion engine into the first selective catalytic reduction device, receiving the exhaust gas from the first selective catalytic reduction device into the exhaust gas heat recovery device and directing the exhaust gas to a heat exchanger in the exhaust gas heat recovery device based on a temperature of the internal combustion engine proximate moving engine components. The method includes adsorbing nitrogen oxides from the exhaust gas via a nitrogen oxide adsorbing catalyst disposed in the heat exchanger and flowing the exhaust gas from the exhaust gas heat recovery device into the second selective catalytic reduction device.

Abstract: An exhaust gas treatment system for an internal combustion engine is provided and includes an exhaust gas conduit, a generator, an electrically heated catalyst (“EHC”) device, and a control module. The exhaust gas conduit is in fluid communication with, and is configured to receive an exhaust gas from the internal combustion engine. The generator operates at a generator speed to produce electrical power. The EHC device is in fluid communication with the exhaust gas conduit. The EHC device includes a monolith structure that is divided into a plurality of segments that define discrete resistive paths. The resistive paths are selectively connected to the generator for receiving electrical power. The control module is in communication with the EHC device, the generator, and the internal combustion engine. The control module includes control logic for determining the generator speed.

Abstract: A waste heat recovery system with an integrated hydrocarbon adsorber for a vehicle having an internal combustion engine that generates exhaust gas containing hydrocarbons, and a catalytic converter, includes an exhaust gas conduit, an exhaust gas heat exchanger, a heat exchanger bypass valve, a coolant circuit with a coolant bypass and a coolant bypass valve, and a controller. The exhaust gas heat exchanger includes at least one channel through which the exhaust gas is flowable, the channel having an interior surface coated with a hydrocarbon adsorbing material configured to adsorb hydrocarbons. The heat exchanger and coolant bypass valves are configured to selectively direct at least a portion of the exhaust gas and the coolant, respectively, to the exhaust gas heat exchanger or to bypass it. They are controlled by the controller such that the hydrocarbons in the exhaust gas are selectively adsorbable by and desorbable from the coating.

Abstract: Following a cold start of a hydrocarbon-fueled engine operated in a lean-burn-combustion mode, several seconds and minutes may be required for the exhaust gas stream to heat exhaust treatment devices in the exhaust system and conduit to their effective operating temperatures. The warm-up period may be particularly long for a NOx reduction catalyst (SCR) located downstream in the exhaust flow system. Accordingly, a bed of absorbent material, such as a suitably sized bed of alumina particles, located upstream of the SCR, is used to temporarily absorb water and NOx from a relatively cold exhaust until the exhaust has suitably heated the SCR to its operating temperature. Then, the warmed exhaust will remove the water and NOx from their temporary storage material and carry them to the reduction catalyst.

Abstract: A system and method is provided for enhancing the performance of an SCR device, particularly by routinely reducing the amount of reductant deposits accumulated in an exhaust gas system, when the reductant is injected at a reduced temperature. The system may include an engine, an exhaust gas system, an SCR device, an injection device, and a controller configured to execute the present method. The controller may be configured to select an initial injection rate and an initial injection temperature for the reductant; estimate the amount of accumulated reductant deposits present within the exhaust gas system; compare the amount of accumulated reductant deposits to a threshold amount of reductant deposits allowable in the exhaust gas system; and initiate a reductant deposit burn-off mode when the amount of accumulated reductant deposits is greater than the threshold amount of reductant deposits allowable in the exhaust gas system.

Abstract: One embodiment of the invention may include a method comprising providing a product comprising a substrate comprising a perovskite catalyst, NOx stored in or on the substrate and particulate matter in or on the substrate; releasing at least some of the stored NOx and oxidizing the released NOx to form NO2, and reacting the NO2 with carbon in the particulate matter to form at least one of CO or CO2.