A catalysed filter for a positive ignition internal combustion engine comprises a porous filtering substrate having a total substrate length coated with a three-way catalyst washcoat composition comprising at least one precious metal selected from the group consisting of rhodium and one or both of platinum and palladium supported on a high surface area oxide, and an oxygen storage component, which composition being axially shared by a first zone comprising inlet surfaces of a first substrate length<total substrate length and a second zone comprising outlet surfaces of a second substrate length<total substrate length, wherein a sum of the substrate length in the first zone and the substrate length in the second zone≧100% and wherein one or both of the following applies: a washcoat loading in the first zone>second zone; and a total precious metal loading in the first zone>second zone.

The present invention relates to a method for the preparation of a molecular sieve of the CHA-type as well as catalytic applications thereof.

A catalyst article having an extruded support having a plurality of channels through which exhaust gas flows during operation of an engine, and a single layer coating or a bi-layer coating on the support, where the extruded support contains a third SCR catalyst, the single layer coating and the bilayer-coating contain platinum on a support with low ammonia storage and a first SCR catalyst. The catalytic articles are useful for selective catalytic reduction (SCR) of NOx in exhaust gases and in reducing the amount of ammonia slip. Methods for producing such articles are described. Methods of using the catalytic articles in an SCR process, where the amount of ammonia slip is reduced, are also described.

A plasma selective catalytic reduction (SCR) system according to an exemplary embodiment of the present invention includes: an exhaust pipe connected to an engine to communicate exhaust gas; a plasma burner installed in a first bypass line connected to the exhaust pipe, and configured to supply fuel to discharged plasma and form flame; a urea solution injector installed in the first bypass line at a rear side of the plasma burner, and configured to inject a urea solution to exhaust gas heated by the flame and generate ammonia; and an SCR catalyst installed in the exhaust pipe at a rear side of the urea solution injector, and configured to reduce a nitrogen oxide included in the exhaust gas with the ammonia.

Systems and methods for an aftertreatment system configured for use with a dual-fuel engine system are described. The method comprises determining an operating mode of the dual-fuel engine. Upon determining that the dual-fuel engine is operating in a dual-fuel mode or a natural gas mode, the dual-fuel engine operates in a stoichiometric operating condition, and the exhaust is received into a three-way catalyst communicatively connected to a selective catalytic reduction catalyst. Upon determining that the dual-fuel engine is not operating in the dual-fuel mode or the natural gas mode, the engine operates in a lean operating condition.

An exhaust system of a work machine is equipped with a first exhaust system, a second exhaust system, and a third exhaust system. The first exhaust system and the third exhaust system are arranged to be in parallel with respective one ends directed in the same direction. In a plan view, the second exhaust system is arranged with the other end side directed in the same direction as the one end sides of the first exhaust system and the third exhaust system to be in parallel with the first exhaust system and the third exhaust system between the first exhaust system and the third exhaust system and, in a side view, is arranged above the first exhaust system and the third exhaust system.

A method for controlling a SCR catalytic converter of a vehicle, comprising a first step of modelling said at least one SCR catalytic converter as a plurality of NH3 storage cells (cell1, cell2, . . . , celln; cell1, cell2 . . . celln, cell1, cell2, . . . , celln), a second step of controlling only a first (cell1) of said plurality of storage cells, according to feedback control based on a reference value, and a third step of adapting said reference value on the basis of a storage level of at least another storage cell of said plurality of storage cells, wherein said first storage cell is arranged at an inlet of said SCR catalytic converter according an exhaust gas circulation.

A provision of assemblies and methods for treating an exhaust gas from an internal combustion engine. The treatment method comprises at least two catalyst stages. The exhaust gas is directed to a first stage catalyst. After the first stage catalyst, the exhaust is passed to an inter-catalyst stage comprising an exhaust cooling process and an oxygen enrichment process. Next, the exhaust is passed to a second stage catalyst for reducing carbon monoxide, ammonia and hydrocarbon concentration in the exhaust gas, before exiting via an outlet.

A honeycomb structure has partition walls defining a plurality of polygonal cells which become through channels for a fluid, a structure end face vertical to an axial direction has at least two cell regions possessing mutually different cell structures and surrounded by circumferential portions, and in the cell regions adjacent to each other, to first partition walls of a first cell structure of one first cell region, second partition walls of a second cell structure of the other or second cell region are tilted.

A honeycomb structure includes a honeycomb structure body including porous partition walls defining a plurality of cells serving as fluid passages extending from an inflow end face to an outflow end face. The partition walls have a porosity of 45 to 65%; the open frontal area of the pores having an equivalent circle diameter of 10 μm or more, of the pores open on the surface of each partition wall, is 20 to 50%; the pore density of the pores having an equivalent circle diameter of 10 μm or more is 200 to 1,000 pores/mm.sup.2; the median opening diameter of the pores having an equivalent circle diameter of 10 μm or more is 40 to 60 μm; the circularity of the pores having an equivalent circle diameter of 10 μm or more is 1.8 to 4.0; and the partition walls have a wet area of 16,500 μm.sup.2 or more.