An as-synthesized microporous material having a CHA structure and containing a first and a second organic structure directing agent (OSDA), wherein the first OSDA has the following general structure of the quaternary ammonium cation is disclosed:

##STR00001##

A microporous crystalline material made from the as-synthesized material is also disclosed. A method of making microporous crystalline material using combined organic structure directing agents is also disclosed. A method of selective catalytic reduction of nitrogen oxides in exhaust gas that comprises contacting exhaust gases, typically in the presence of ammonia, urea, an ammonia generating compound, or a hydrocarbon compound, with an article comprising the disclosed microporous crystalline is further disclosed.

An oxidation catalyst for treating an exhaust gas from a diesel engine, which oxidation catalyst comprises: a first washcoat region comprising platinum (Pt), manganese (Mn) and a first support material; a second washcoat region comprising a platinum group metal (PGM) and a second support material; and a substrate having an inlet end and an outlet end; wherein the second washcoat region is arranged to contact the exhaust gas at the outlet end of the substrate and after contact of the exhaust gas with the first washcoat region.

Certain catalytic articles, systems or methods provide for excellent NOx conversion and are especially suitable for low temperature NOx conversion. The articles, systems and methods are suitable for instance for the treatment of exhaust gas of diesel engines. Certain articles or systems contain an upstream SCR composition and a downstream LNT composition. The substrate(s) may advantageously be electrically heated.

A catalyst for direct decomposition removal of NOx from an exhaust gas stream to N.sub.2 and O.sub.2, the catalyst comprising a dual dispersed supported metal oxide material, which comprises MOx—CuOx dispersed on a CO.sub.3O.sub.4 spinel oxide support, wherein M is selected from the group consisting of Zn, Ce, Mg, Tb, and Gd. The dual dispersed supported metal oxide catalysts have good activity and selectivity for N.sub.2.

A diesel-emissions reduction unit having an inlet adapted to receive an exhaust stream of the diesel engine; a diesel oxidation trap catalyst located adjacent the inlet; a dosing controller and an injection lance arranged to meter aqueous NH.sub.3 into the exhaust stream; a NOx concentration sensor and a NH.sub.3 concentration sensor with at least one oxidation catalyst panel arranged to isolate the NOx concentration sensor from NH.sub.3 in the exhaust stream; and an exhaust heater arranged to heat the exhaust stream of the diesel engine toward the inlet of the diesel emissions reduction unit.

Provided are a selective reducing catalyst for diesels and a diesel exhaust gas purification apparatus in which deterioration of NO.sub.x removal performance due to phosphorus poisoning is less likely to occur.

The selective reducing catalyst for diesels is arranged in a diesel engine, adsorbs ammonia and brings the ammonia into contact with nitrogen oxides in an exhaust gas discharged from a diesel engine to perform reduction, the selective reducing catalyst comprises: a catalyst carrier; a catalyst region provided on at least the catalyst carrier; and a phosphorus trapping region provided on at least the catalyst region, wherein the catalyst region comprises one or more selected from the group consisting of a zeolite-based catalyst containing at least zeolite and a transition metal element supported on the zeolite, a W—Ce—Zr composite oxide-based catalyst, and a vanadium-based catalyst, and the phosphorus trapping region comprises at least one or more selected from the group consisting of alumina and a rare earth-based basic oxide.

Systems, apparatuses, and methods include 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 concentration of one or more of NO and NO.sub.2 at or proximate an inlet of the exhaust aftertreatment system and based on a dynamic model of the SCR catalyst, information indicative of a concentration of NOx at or proximate an outlet of the exhaust aftertreatment system, and information indicative of an amount of stored reductant in the SCR catalyst. The controller is further structured to command the at least one reductant doser to increase, decrease, or maintain an amount of reductant provided to the exhaust gas based on the determined concentration of one or more of NO and NO.sub.2 in the exhaust gas.

A composite oxidation catalyst (18, 20) for use in an exhaust system for treating an exhaust gas produced by a vehicular compression ignition internal combustion engine (30) and upstream of a particulate matter filter (44, 50) in the exhaust system comprises a substrate (5) having a total length L and a longitudinal axis and having a substrate surface extending axially between a first substrate end (I) and a second substrate end (O); and three or more catalyst washcoat zones (1, 2, 3; or 1, 2, 3, 4) arranged axially in series on and along the substrate surface, wherein a first catalyst washcoat zone (1) having a length L.sub.1, wherein L.sub.1<L, is defined at one end by the first substrate end (I) and at a second end by a first end (19, 21) of a second catalyst washcoat zone (2) having a length L.sub.2, wherein L.sub.2<L, wherein the first catalyst washcoat zone (1) comprises a first refractory metal oxide support material and two or more platinum group metal components supported thereon comprising both platinum and palladium at a weight ratio of platinum to palladium of ≥1; the second catalyst washcoat zone (2) comprises a second refractory metal oxide support material and one or more platinum group metal components supported thereon; and a third catalyst washcoat zone (3) comprising a third refractory metal oxide support material and one or more platinum group metal components supported thereon is defined at a second end thereof by the second substrate end (O), wherein a total platinum group metal loading in the first catalyst washcoat zone (1) defined in grams of platinum group metal per cubic foot of substrate volume (g/l) (g/ft.sup.3) is greater than a total platinum group metal loading in the second catalyst washcoat zone (2), wherein a total platinum group metal loading in the third catalyst washcoat zone (3) defined in grams of platinum group metal per cubic foot of substrate volume (g/l) (g/ft.sup.3) is less than the total platinum group metal loading in the second catalyst washcoat zone (2) and wherein the first catalyst washcoat zone (1) comprises one or more first alkaline earth metal components supported on the first refractory metal oxide support material.

An exhaust treatment system includes an exhaust line, a series of emission treatment units, and an electronic control unit. The series of emission treatment units includes a catalytic unit, a particulate filter unit, an oxidation catalytic unit, a hydrogen injection unit, and a Lean NOx Trap (LNT) for trapping select emissions. A method of operating an exhaust treatment system includes introducing a fuel to a combustion engine of a motor vehicle, directing emissions from the combustion engine to an exhaust line, and passing the emissions in the exhaust line through a series of emission treatment units on the exhaust line. The method further includes injecting hydrogen into the exhaust line via a hydrogen injection unit, where an amount of hydrogen gas injected from a hydrogen inlet line reduces the trapped emissions in the LNT to an inert gas.

The present invention relates to a catalyst comprising a carrier substrate of the length L extending between substrate ends a and b and three washcoat zones A, B and C wherein washcoat zone A comprises one or more first platinum group metals and extends starting from substrate end a over a part of the length L, washcoat zone C comprises one or more first platinum group metals and extends starting from substrate end b over a part of the length L, and washcoat zone B comprises the same components as washcoat zone A and in addition, one or more second platinum group metals and extends between washcoat zones A and C, wherein L=L.sub.A+L.sub.B+L.sub.C, wherein L.sub.A is the length of washcoat zone A, L.sub.B is the length of substrate length B and L.sub.C is the length of substrate length C.