A NO.sub.x trap catalyst is disclosed. The NO.sub.x trap catalyst comprises a noble metal, a NO.sub.x storage component, a support, and a first ceria-containing material. The first ceria-containing material is pre-aged prior to incorporation into the NOx trap catalyst, and may have a surface area of less than 80 m.sup.2/g. The invention also includes exhaust systems comprising the NO.sub.x trap catalyst, and a method for treating exhaust gas utilizing the NO.sub.x trap catalyst.

A controller for an exhaust-gas purification system of a vehicle, may be configured to activate a regeneration of a diesel particulate filter when an amount of exhaust particles inside the diesel particulate filter exceeds a predetermined threshold level, and to activate a regeneration of an NOx trap catalyst at least when an amount of NOx adsorbed to the NOx trap catalyst exceeds a predetermined NOx threshold value, and wherein the controller is further designed to activate the regeneration the NOx trap catalyst at least sometimes at a beginning of and/or during the regeneration of the diesel particulate filter. The present invention further provides a corresponding method of operating an exhaust-gas purification system of a vehicle.

A honeycomb filter including: a honeycomb structure having a porous partition wall provided surrounding a plurality of cells; and a plugging portion disposed to seal either one end portion on the inflow or the outflow end face side of the cells, wherein the cell in which the plugging portion is provided at the outflow end face side and the inflow end face side is open is defined as an inflow cell, the cell the plugging portion is provided at the inflow end face side and the outflow end face side is open is defined as an outflow cell, the honeycomb structure further has a trapping layer for the particulate matter on an inner surface side of the partition wall, the trapping layer includes a portion composed of a sintered body of CeO.sub.2 particles on at least a surface layer, and the average particle diameter is 1.1 m or less.

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.

A system includes a controller for an exhaust aftertreatment system including a SCR catalyst in exhaust gas-receiving communication with an engine and at least one reductant dosing system structured to provide reductant to the exhaust gas. The controller is structured to determine a ratio of NO to NO.sub.2 at or proximate an inlet of the SCR catalyst. The controller is further structured to command the at least one reductant dosing system to increase, decrease, or maintain an amount of reductant provided to the exhaust gas based on comparing the ratio of NO to NO.sub.2 to a previous NO to NO.sub.2 ratio.

An engine exhaust aftertreatment system is disclosed. The system may comprise: an internal combustion engine having an intake passage and an exhaust passage; a turbocharger fluidly connected to the internal combustion engine, the turbocharger including a compressor and a turbine, the compressor being in fluid communication with the intake passage, and the turbine being in fluid communication with the exhaust passage; a reductant injector situated downstream of the turbocharger, wherein the reductant injector is closely coupled to the turbocharger such that a reductant is injected into an exhaust flow of the turbocharger; a first container downstream of the reductant injector, the first container including a multi-functional catalyst (MFC); and a second container downstream of the first container, the second container including a selective catalytic reduction (SCR) component and an Ammonia catalyst (AMOx) component.

A correction method of NOx purifying efficiency of SDPF includes: measuring a temperature change per unit time inside the SDPF, determining whether the temperature change per unit time inside the SDPF is below a first predetermined value, determining whether a difference between a maximum value and a minimum value of temperature of respective parts inside the SDPF is below a second predetermined value if the temperature change per unit time inside the SDPF is below the first predetermined value, determining whether a temperature inside the SDPF is in a low temperature region if the difference between the maximum value and the minimum value of temperature of the respective parts inside the SDPF is below the second predetermined value, and performing a low temperature region correction if the temperature inside the SDPF is in the low temperature region.

The present disclosure relates to a hydraulic circuit system for forced regeneration of a diesel particulate filter, and more particularly, to a hydraulic circuit system for forced regeneration of a diesel particulate filter (DPF), which prevents a working machine from being operated when the diesel particulate filter is forcedly regenerated by combusting particulate matters (PM) in a case in which the diesel particulate filter is installed in a construction machine with a diesel engine and particulate matters contained in exhaust gas are collected in the diesel particulate filter.

Systems and methods are provided for feedgas diagnostics in a selective catalytic reduction (SCR) system. An example electronic system may be part of on-board diagnostic (OBD) functionality in a diesel fuel vehicle and may comprise circuits for defining and managing system conditions for hydrocarbon dosing, adjusting the dosing to a diesel oxidation catalyst (DOC) while the system is in operation, and defining a diagnostic framework based at least on exothermic properties of various components of a DOC such that a DOC may be monitored for failure and/or end of useful life (EUL). The electronic system may include a tuning circuit for calibrating the diagnostic framework.

A NO.sub.x absorber catalyst for treating an exhaust gas from a diesel engine. The NO.sub.x absorber catalyst comprises a first NO.sub.x absorber material comprising a molecular sieve catalyst, wherein the molecular sieve catalyst comprises a noble metal and a molecular sieve, and wherein the molecular sieve contains the noble metal; a second NO.sub.x absorber material comprising palladium (Pd) supported on an oxide of cerium; and a substrate having an inlet end and an outlet end.