In an exhaust system for a motor vehicle having an exhaust treatment device for after-treating exhaust gas of a combustion engine of the motor vehicle, the exhaust gas treatment device includes a first SCR catalyst, which has a zeolite material containing copper, an ammonia slip catalyst, which is arranged downstream of the first SCR catalyst, and a particulate filter. A second SCR catalyst, which has an SCR catalyst material containing vanadium, is arranged upstream of the first SCR catalyst.

The present invention relates to a catalytically coated wall-flow filter, to a method for the production thereof and to the use thereof in order to reduce s harmful exhaust gases of an internal combustion engine.

A coated ceramic honeycomb body comprising a honeycomb structure comprising a matrix of intersecting porous walls forming a plurality of axially-extending channels, at least some of the plurality of axially-extending channels being plugged to form inlet channels and outlet channels, wherein a total surface area of the outlet channels is greater than a total surface area of the inlet channels, and wherein a catalyst is preferentially located within the outlet channels, and preferentially disposed on non-filtration walls of the outlet channels. Methods and apparatus configured to preferentially apply a catalyst-containing slurry to the outlet channels and non-filtration walls are provided, as are other aspects.

An exhaust gas purifier is disposed in an exhaust gas passage of an engine, and includes: a DPF for capturing PM contained in exhaust gas; an SCR catalyst provided downstream of the DPF in a direction of flow of the exhaust gas, and for reducing NO.sub.x contained in the exhaust gas for purification in the presence of NH.sub.3; an injection unit provided between the DPF and the SCR catalyst, and for supplying urea to the SCR catalyst so as to supply NH.sub.3 to the SCR catalyst; and an AMOX provided downstream of the SCR catalyst in the direction of flow of the exhaust gas, and for removing NH.sub.3 having passed through the SCR catalyst. The DPF does not contain Pt or Pd, and contains Rh. The AMOX contains Pt.

The present disclosure generally provides selective catalytic reduction (SCR) catalyst compositions, catalyst articles and catalyst systems including such catalyst articles for treating engine exhaust gas. In particular, the SCR catalyst composition includes a first zeolite and a second zeolite and has not been subjected to temperatures above 650° C. The first zeolite includes a promoter metal and has a first framework structure and at least a portion of the second zeolite is in a form selected from H.sup.+ form, NH.sub.4.sup.+ form, alkali metal form, alkaline earth metal form, and combinations thereof and has a second framework structure. The first framework structure and the second framework structure are different.

An exhaust gas purification apparatus for an internal combustion engine includes a particulate filter, an air fuel ratio sensor to detect an air fuel ratio of exhaust gas at the downstream side of the filter, and a controller configured to: change an air fuel ratio, determine whether an amount of particulate matter (PM) deposited in an interior of a partition wall of the filter is equal to or smaller than a predetermined amount, and estimate a maximum storable oxygen amount of the catalyst from a change of the air fuel ratio of exhaust gas at the time when the air fuel ratio of the exhaust gas is changed, in cases where the amount of PM deposited in the interior of the partition wall of the filter is equal to or smaller than the predetermined amount.

A mixer for an exhaust system of an internal combustion engine includes a mixer housing (40) with an inflow opening central axis (LE) and with an outflow opening (38). A first flow duct (48) following the inflow opening (24) in the mixer housing (40) and a second flow duct (50) lead parallel to one another to a third flow duct (54) and open into same. The third flow duct (54) leads to the outflow opening (38). The first flow duct (48) and the second flow duct (50) are provided between an outer wall (16) of the mixer housing (40) and a flow divider wall (36) enclosed by the outer wall (16), and the third flow duct (54) is enclosed by the flow divider wall (36).

Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

A method of synthesis for an aluminophosphate-based zeolite membrane includes a steps of preparing a mixed solution with a pH greater than or equal to 6 and less than or equal to 9 by mixing an acidic phosphorous source with an alkali source, a steps of preparing a starting material solution by adding and mixing an aluminum source to the prepared mixed solution, and a steps of synthesizing an aluminophosphate-based zeolite membrane by hydrothermally synthesizing the starting material solution.

The present disclosure features a high metal cation content zeolite-based binary catalyst (e.g., a high copper and/or iron content zeolite-based binary catalyst, where the zeolite can be a chabazite) for NO.sub.x reduction, having relatively low N.sub.2O make, and having low corresponding metal oxide content; where the metal in the metal oxide corresponds to the metal of the metal cation. The present disclosure also describes the synthesis of the zeolite-based binary catalyst having high metal cation content.