An emissions control substrate for treating exhaust from an engine including a plurality of hexagonal cells extending between a first end and a second end of the substrate. Wash coats are at an interior of the hexagonal cells. At an inner region of the substrate through which a longitudinal axis of the emissions control substrate extends, for every group of three adjacent hexagonal cells of the plurality of hexagonal cells two are plugged at the first end and open at the second end, and one is open at the first end and plugged at the second end. At an outer region of the substrate surrounding the inner region, for every group of three adjacent hexagonal cells of the plurality of hexagonal cells, one is plugged at the first end and open at the second end, and two are open at the first end and plugged at the second end.

An exhaust treatment system comprising: a first oxidation catalyst to oxidize nitrogen compounds and/or hydrocarbon compounds in said exhaust stream; a first dosage device downstream of said first oxidation catalyst to supply a first additive into said exhaust stream; a first reduction catalyst device downstream of said first dosage device for reduction of nitrogen oxides in said exhaust stream using said first additive; a particulate filter, comprising a catalytically oxidizing coating downstream of said first reduction catalyst device to catch soot particles and oxidize one or several of nitrogen oxide and incompletely oxidized carbon compounds in said exhaust stream; a second dosage device downstream of said particulate filter to supply a second additive into said exhaust stream; and a second reduction catalyst device downstream of said second dosage device for a reduction of nitrogen oxides in said exhaust stream, using at least one of said first and second additive.

The present invention relates to a porous alpha-SiC-containing shaped body with a gas-permeable, open-pored pore structure comprising platelet-shaped crystallites which are connected to form an interconnected, continuous skeletal structure, wherein the skeletal structure consists of more than 80 wt.-% alpha-SiC, relative to the total weight of SiC, a process for producing same and its use as a filter component.

An exhaust gas purification system comprises a first fuel supply unit to supply fuel to exhaust gas flowing in an exhaust passage by a supply valve arranged in the exhaust passage, and a second fuel supply unit to supply fuel to exhaust gas by adjusting a fuel injection condition, wherein in a temperature raising stage of the NOx SCR catalyst associated with the exhaust gas temperature raising processing, first control is performed in which fuel is supplied by the first fuel supply unit, and in a temperature holding stage of the NOx SCR catalyst associated with the exhaust gas temperature raising processing, at least second control is performed in which the ratio of an amount of fuel supply by the second fuel supply unit with respect to an amount of fuel supply by the first fuel supply unit becomes higher in comparison with that when performing the first control.

An exhaust gas control system for an internal combustion engine, before execution of a filter regeneration process, executes a pre-regeneration process that is a process of raising a temperature of a filter to a second target temperature lower than a first target temperature and increasing the concentration of NO.sub.2 contained in exhaust gas flowing into the filter for a predetermined period. An execution time of the filter regeneration process when a physical quantity that correlates with a speed of change in a detected value of a differential pressure sensor during execution of the pre-regeneration process is large is shorter than an execution time of the filter regeneration process when the physical quantity is small.

Method for removal of soot, ash and metals or metal compounds, together with removal of NOx and SOx being present in process off-gasses or engine exhaust gasses.

An exhaust gas after-treatment unit includes a first catalytic converter, a particle filter arranged downstream of the first catalytic converter, and a second catalytic converter arranged downstream of the particle filter and which is a selective catalytic reduction (SCR) catalytic converter. The first catalytic converter is a combination catalytic converter including a first catalytic converter part which is an SCR catalytic converter, a second catalytic converter part arranged downstream of the first catalytic converter part which is an ammonia slip catalytic converter and has a noble metal layer with a first noble metal content, a third catalytic converter part arranged downstream of the second catalytic converter part which is an oxidation catalytic converter and has a noble metal layer with a second noble metal content, and an SCR layer arranged on the noble metal layers and extending over the entire length of the second and third catalytic converter parts.

A method for determining the aging of an oxidation catalyst in an exhaust gas aftertreatment system of an internal combustion engine, having the following steps: ascertaining a soot burn rate of a particle filter of the exhaust gas aftertreatment system; adapting a function having at least one adaptation parameter to the soot burn rate dependent on at least one variable, a value of the adaptation parameter depending on an aging of the oxidation catalyst; and determining the aging of the oxidation catalyst using the adaptation parameter value ascertained by adapting the function.

Methods and systems are provided for treatment of an exhaust stream that comprises nitrogen oxides NO.sub.x. The method comprises supplying a first additive to the exhaust stream as a first reduction of a first amount of nitrogen oxides NO.sub.x.sub._.sub.1 reaching a first device, arranged to impact the first amount of nitrogen oxides NO.sub.x.sub._.sub.1. The method also comprises supplying a second additive to the exhaust stream, which is used as a second reduction of a second amount of nitrogen oxides NO.sub.x.sub._.sub.2 reaching a second device, arranged to reduce the second amount of nitrogen oxides NO.sub.x.sub._.sub.2. At least one of the first supply and the second supply is controlled, based on a total ability for the first device to provide the first reduction, and for the second device to provide the second reduction, so that a required total reduction on the nitrogen oxides NO.sub.x in the exhaust stream is provided.

An exhaust treatment system comprising: a first oxidation catalyst to oxidize nitrogen- and/or hydrocarbon compounds in an exhaust stream; a first dosage device downstream of said first oxidation catalyst to supply a first additive into said exhaust stream; a first reduction catalyst device, arranged downstream of said first dosage device, including a slip-catalyst primarily for reduction of nitrogen oxides (NOx), and secondarily for oxidation of additive; a second oxidation catalyst arranged downstream of said first reduction catalyst; a particulate filter arranged downstream of said oxidation catalyst; a second dosage device, arranged downstream of said particulate filter to supply a second additive into said exhaust stream; and a second reduction catalyst device, arranged downstream of said second dosage device for reduction of nitrogen oxides in said exhaust stream, with the use of at least one of said first and said second additive.