Abstract: A method of managing vapors generated from an ammonia-containing reductant delivery system for a vehicle is described. The method may include storing ammonia containing vapors generated in the reductant delivery system during engine-off and then purging said stored ammonia into an exhaust of the engine to react in a catalyst in the exhaust flow during engine operation.

Abstract: A method for controlling emissions from an engine includes reducing trapped nitrogen oxides to ammonia on an LNT catalyst while concurrently oxidizing soot accumulated on the LNT catalyst, and, flowing the ammonia so formed to an SCR catalyst.

Abstract: Systems and methods for reducing NOx emissions using a branched exhaust system with a first and second turbine including an emission-control device containing a zeolite, are described. In one example approach, a method comprises: during a first duration when exhaust temperature is below a first temperature threshold, directing exhaust gas through the second turbine and the emission-control device, and adjusting the second turbine to control intake boost; and during a second duration following the first, directing exhaust gas through the first turbine, and adjusting the first turbine to control intake boost. In this way, the first and second turbines may provide a greater degree of boost control in order to reduce boost fluctuations while enabling storing cold start NOx emissions for later reduction.

Abstract: A diesel engine exhaust treatment system and method is provided which includes a platinum group metal trapping device (16) comprising cerium oxide or a perovskite material positioned between a diesel oxidation catalyst and an SCR catalyst. The platinum group metal trapping device traps trace amounts of platinum group metals which may be released from the diesel oxidation catalyst during engine operation and prevents them from accumulating on the SCR catalyst, preventing potential contamination of the SCR catalyst as well as ensuring that the performance of the SCR catalyst is uninhibited.

Abstract: A method is provided for managing vapor generation in a reductant storage and delivery system. In one example, urea vapors generated from liquid in a storage device are temporarily stored and later purged to the exhaust system of the engine.

Abstract: The present invention relates to an emission control system for reducing gases from the exhaust of a combustion engine. In at least one embodiment, the emission control system includes an exhaust passage for transporting the exhaust from the combustion engine, and a particulate filter and selective catalytic reduction (SCR/PF) unit disposed within the passage, with the unit having a plurality of spaced filter walls extending axially along the passage and selective catalytic reduction catalyst variably loaded on the unit to provide a more uniform pressure drop relative to a unit having uniformly loaded catalyst.

Abstract: An exemplary emission treatment system for reducing gases from the exhaust of an engine includes an exhaust passage for transporting the exhaust from the engine. A selective catalytic reduction (SCR) catalyst is disposed within the passage, and an oxidation catalyst is disposed in the passage upstream of the SCR catalyst. The oxidation catalyst has noble metal, with at least 90 wt. % of the metal comprising palladium (Pd).

Abstract: A method of operating a reductant delivery and storage system of a vehicle, comprising of storing an ammonia-containing fluid in a first storage device, generating ammonia vapors in the first storage device, storing said generated ammonia vapors in a second storage device, purging said stored vapors from the second storage device to an exhaust of the engine, and relieving pressure or vacuum build-up during at least one of said storing and purging is provided via an atmospheric vent coupled in the reductant delivery and storage system.

Abstract: According to one aspect of the present invention, a catalyst assembly is provided for treating an exhaust from an engine. In one embodiment, the catalyst assembly includes a first catalyst material catalytically active at a first temperature and loaded at a first catalyst material loading, the first catalyst material including a first base metal loading, and a second catalyst material catalytically active at a second temperature lower than the first temperature and loaded at a second catalyst material loading, the second catalyst material including a second base metal loading, wherein the second base metal loading is higher than the first base metal loading.

Abstract: The present invention relates to an emission treatment system for reducing gases from the exhaust of an engine. In at least one embodiment, the emission treatment system includes an exhaust passage for transporting the exhaust from the engine, a selective catalytic reduction (SCR) catalyst disposed within the passage, and an oxidation catalyst disposed in the passage upstream of the SCR catalyst, with the oxidation catalyst having metal, with at least 90 wt. % of the metal comprising palladium (Pd).

Abstract: The present invention relates to an emission control system for reducing gases from the exhaust of a combustion engine. In at least one embodiment, the emission control system includes an exhaust passage for transporting the exhaust from the combustion engine, and a particulate filter and selective catalytic reduction (SCR/PF) unit disposed within the passage, with the unit having a plurality of spaced filter walls extending axially along the passage and selective catalytic reduction catalyst variably loaded on the unit to provide a more uniform pressure drop relative to a unit having uniformly loaded catalyst.

Abstract: Systems and methods are provided for reducing exhaust NOx species using a monolith substrate having a plurality of channels configured with radially varying cell density. The configuration enables radial reductant mixing, thereby improving mixing and atomization of an injected reductant with an exhaust gas stream.

Abstract: A motor-vehicle engine system comprises a first DOC configured to receive exhaust from an engine and an SCR device coupled downstream of the first DOC in a flow direction of the exhaust. The system further comprises a second DOC coupled downstream of the SCR device. The system takes advantage of hydrocarbon sorption in the SCR catalyst that is a function of temperature to enable reduced hydrocarbon emissions via oxidation at the second DOC.

Abstract: An emission control system capable of remediating an exhaust from an internal combustion engine and having an exhaust passage, an oxidation catalyst, a reducing agent and a source of the reducing agent cooperating with an aperture in the exhaust passage. The aperture is disposed downstream of the oxidation catalyst. The system also includes a mixer arranged within the exhaust passage downstream of the aperture. The mixer includes a plurality of mixing elements. The mixer also includes a coating capable of hydrolyzing the reducing agent. At least a portion of the mixing elements which have a thermal conductivity greater than 8 W/m/° K. The system includes a selective catalytic reduction (SCR) catalyst disposed downstream from the mixer.

Abstract: A method for controlling emissions from an engine includes reducing trapped nitrogen oxides to ammonia on an LNT catalyst while concurrently oxidizing soot accumulated on the LNT catalyst, and, flowing the ammonia so formed to an SCR catalyst.

Abstract: Systems and methods for reducing NOx emissions using a branched exhaust system with a first and second turbine including an emission-control device containing a zeolite, are described. In one example approach, a method comprises: during a first duration when exhaust temperature is below a first temperature threshold, directing exhaust gas through the second turbine and the emission-control device, and adjusting the second turbine to control intake boost; and during a second duration following the first, directing exhaust gas through the first turbine, and adjusting the first turbine to control intake boost. The emission-control device may be purged when exhaust temperature is above a second temperature threshold higher than the first temperature threshold, where during the second duration exhaust gas does not flow through the emission-control device.

Abstract: A hydrocarbon and NOx trap and related apparatus and methods for reducing cold-start NOx emissions from an engine are provided. In one embodiment a trap includes a first, topmost layer, exposed to an exhaust gas flow path of exhaust gases from an engine, the first layer comprising a zeolite, a second layer, substantially covered by the top most layer, the second layer comprising a NOx adsorbing material and a monolithic substrate, directly supporting the second layer and indirectly supporting the first layer, the substrate providing a substantially rigid structure of the trap.

Abstract: Methods and systems for controlling and/or diagnosing an emission control system of a vehicle having a first SCR region upstream of a second SCR region are provided herein. One exemplary method includes, indicating degradation based on a first SCR region performance during a first condition; and indicating degradation based on a second SCR region performance during a second condition, the first condition different than the second condition. In this way, different levels of degradation among different SCR regions may be used to indicate emissions levels have increased above a threshold value, for example.

Abstract: A method of operating a reductant delivery and storage system of a vehicle, comprising of storing an ammonia-containing fluid in a first storage device, generating ammonia vapors in the first storage device and storing said generated ammonia vapors in a second storage device, purging said stored vapors from the second storage device to an exhaust of the engine, delivering said ammonia-containing fluid to said exhaust of the engine, and adjusting at least one of an amount of ammonia-containing fluid delivered and an amount of vapors purged to said exhaust based on the other of said at least one of said amount of ammonia-containing fluid delivered and said amount of vapors purged to said exhaust.

Abstract: A method of managing vapors generated from an ammonia-containing reductant delivery system for a vehicle is described. The method may include storing ammonia containing vapors generated in the reductant delivery system during engine-off and then purging said stored ammonia into an exhaust of the engine to react in a catalyst in the exhaust flow during engine operation.