Methods and systems are provided for a low temperature NOx adsorber (LTNA). In one example, a method includes initiating a desulfation of an LTNA responsive to an estimated sulfur exposure exceeding a threshold, the desulfation including heating the LTNA to a first threshold temperature while maintaining an exhaust oxygen level above a threshold level throughout the entire desulfation.

The present disclosure relates to a method of compacting an ash deposited in a particulate filter for a vehicle exhaust gas system, the method comprising the steps of: a) providing a low-temperature melting salt to the particulate filter, thereby forming a mixture of the ash and the low-temperature melting salt: and b) bringing the particulate filter to a compaction temperature, thereby compacting the mixture of the ash and the low-temperature melting salt. The disclosure further relates to engine oils, dosage products, engine systems and vehicles for implementing such a method.

An aftertreatment system includes a first pipe section in fluid communication with an exhaust manifold on an internal combustion engine. A first aftertreatment device includes a housing and a porous substrate having substrate walls defining a plurality of flow channels including first channels obstructed at a first end of the substrate and second channels obstructed at a second end of the substrate opposite the first end. The first and second channels are interleaved and internal pore surfaces in the porous substrate form a plurality of internal pores. A passive NOx adsorption catalyst is deposited on the substrate walls and internal pore surfaces such that the mean porosity of the porous substrate is not greater than a particulate matter secondary grain size. A second aftertreatment device having an inlet is in fluid communication with the outlet of the first aftertreatment device.

An apparatus for exhaust gas purification comprises a filter function. The apparatus includes a gas-permeable substrate which forms a wall-flow filter that forms channels. The channels are sealed at least at one end and exhaust gas is flowable through the channels and gas-permeable channel walls of the channels formed from the substrate. A surface of the substrate is provided with an oxygen-storing coating. The mass of an oxygen-storing material coated on the surface of the substrate on an outflow side is higher than the mass of the oxygen-storing material coated on the surface of the substrate on an inflow side.

An exhaust gas flow after-treatment (AT) system includes first AT device and a second AT device in fluid communication with and positioned in the flow of exhaust gas downstream of the first AT device. The AT system also includes an exhaust passage for carrying the flow of exhaust gas from the first AT device to the second AT device and an injector for introducing a reductant into the exhaust passage. The AT system additionally includes a variable-position mixer arranged within the exhaust passage downstream of the injector. Furthermore, the AT system includes a mechanism configured to regulate the variable-position mixer between and inclusive of a first mixer position configured to increase a swirling motion and turbulence in the exhaust gas flow within the exhaust passage to thereby mix the reductant with the exhaust gas flow, and a second mixer position configured to reduce a backpressure generated by the mixer.

An exhaust gas flow after-treatment (AT) system includes first AT device and a second AT device in fluid communication with and positioned in the flow of exhaust gas downstream of the first AT device. The AT system also includes an exhaust passage for carrying the flow of exhaust gas from the first AT device to the second AT device and an injector for introducing a reductant into the exhaust passage. The AT system additionally includes a variable-position mixer arranged within the exhaust passage downstream of the injector. Furthermore, the AT system includes a mechanism configured to regulate the variable-position mixer between and inclusive of a first mixer position configured to increase a swirling motion and turbulence in the exhaust gas flow within the exhaust passage to thereby mix the reductant with the exhaust gas flow, and a second mixer position configured to reduce a backpressure generated by the mixer.

A catalyst article including a substrate with an inlet side and an outlet side, a first zone and a second zone, where the first zone includes a passive NOx adsorber (PNA), and an ammonia slip catalyst (ASC) comprising a platinum group metal on a support and a first SCR catalyst; where the second zone includes a catalyst selected from the group consisting of a diesel oxidation catalyst (DOC) and a diesel exotherm catalyst (DEC); and where the first zone is located upstream of the second zone. The first zone may include a bottom layer with a blend of: (1) the platinum group metal on a support and (2) the first SCR catalyst; and a top layer with a second SCR catalyst, the top layer located over the bottom layer.

A reagent dosing system for dosing a reagent into the exhaust gas stream of an internal combustion engine includes a reagent tank for storing a supply of reagent; an injector module including an atomizing dispenser and a positive-displacement metering pump which draws reagent from the reagent tank and delivers it to the dispenser; a supply line coupling the reagent tank to the injector module; a dosing control unit operable to control the injector module to inject reagent into the exhaust gas stream; and an additional priming pump arranged, in use, to urge reagent along the supply line toward the injector module under selected conditions.

An exhaust treatment system includes an engine, an exhaust line in fluid communication with the engine, a three-way catalyst downstream of the engine on the exhaust line, a particulate filter downstream of and proximate to the three-way catalyst on the exhaust line, and a sorbent unit comprising a first sorbent and a second sorbent downstream of the three-way catalyst and the particulate filter on the exhaust line. The first sorbent and the second sorbent are proximate to a tailpipe of the exhaust line. A method of treating an exhaust emission from an internal combustion engine during an engine cold-start is also described.

The present disclosure is directed to an emission treatment system for NO.sub.x abatement in an exhaust stream of a lean burn engine. The emission treatment system includes a lean NO.sub.x trap (LNT) in fluid communication with and downstream from the lean burn engine and a low-temperature NO.sub.x adsorber (LT-NA) in fluid communication with and downstream of the LNT. Further provided is a method for abating NO.sub.x in an exhaust stream from a lean burn engine utilizing the disclosed system.