An improved SCRoF (selective catalytic reduction on filter) device for treating exhaust from an internal combustion engine. The filter has numerous entry and exit channels. Exhaust enters the entry channels and flows through side walls into the exit channels. Relative to the exhaust flow path, these side walls are coated on the downstream side with a ceria-based catalyst and on the upstream side with a Cu-zeolite catalyst. This allows the filter to optimally achieve both particulate matter oxidation and NOx reduction, respectively.

The present invention is directed to a method of preparing a synthetic crystalline material, designated as JMZ-12, with a framework built up by the disorder AEI and CHA structures, substantially free of framework phosphorous and prepared preferably in the absence of halides such as fluoride ions. Such method comprises the step of heating a reaction mixture under crystallization conditions for a sufficient period to form a disordered zeolite having both CHA and AEI topologies, wherein the reaction mixture comprises at least one source of aluminum, at least one source of silicon, a source of alkaline or alkaline-earth cations, and a structure directing agent containing at least one source of quaternary ammonium cations and at least one source of alkyl-substituted piperidinium cations in a molar ratio of 0.20 to about 1.4. The resulting zeolites are useful as catalysts, particularly when used in combination with exchanged transition metal(s) and, optionally, rare earth metal(s).

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 process for preparing an oxidic material comprising a zeolitic material having framework type AEI and a framework structure comprising a tetravalent element Y, a trivalent element X, and O, the process comprising preparing a synthesis mixture comprising water, a source of Y, a source of X comprising sodium, an AEI framework structure directing agent, and a source of sodium other than the source of X; and heating the synthesis mixture obtained from (i) to a temperature in the range of from 100 to 180° C. and keeping the synthesis mixture under autogenous pres-sure at a temperature in this range for a time in the range of at least 6 h, obtaining the oxidic material comprising a zeolitic material having framework type AEI and a framework structure comprising a tetravalent element Y, a trivalent element X, and O, comprised in its mother liquor; wherein the AEI framework structure directing agent according to (i) comprises a N, N-diethyl-2,6-dimethylpiperidinium cation.

JMZ-1, a zeolite having a CHA structure and containing trimethyl(cyclohexylmethyl)ammonium cations as a structure directing agent is described. A calcined zeolite, JMZ-1C, that does not contain a structure directing agent, is also described. Metal containing JMZ-1C has improved SCR activity compared to CHA-containing zeolites having the same metal loading and comparable silica:alumina ratios (SAR). Methods of preparing JMZ-1, JMZ-1C and metal containing calcined counterparts of JMZ-1C are described along with methods of using JMZ-1C and metal containing calcined counterparts of JMZ-1C in treating exhaust gases.

A method includes: providing a SCR system comprising a SCR catalyst; heating the SCR system to a temperature greater than 500 degrees Celsius for a predetermined time so as to increase sulfur resistance of the SCR catalyst; and installing the SCR system in an aftertreatment system.

Provided is a β-zeolite that has an SiO.sub.2/Al.sub.2O.sub.3 ratio of less than 20 but yet is comparable or superior in heat resistance to conventional β-zeolites having SiO.sub.2/Al.sub.2O.sub.3 ratio of 20 or greater. This β-zeolite is characterized in that: in powder X-ray diffractometry using a CuKα-ray as a ray source, the full width at half maximum of a powder X-ray diffraction peak on the (302) plane is 0.15-0.50 inclusive; and the molar ratio of silica to alumina is less than 20.0. Preferably, the β-zeolite is obtained by a production method which comprises a crystallization step for crystallizing a composition comprising an alumina source, a silica source, an alkali source, a tetraethylammonium cation source and water, characterized in that the composition contains potassium and the molar ratio of potassium to silica exceeds 0.04.

A process for the preparation of an extra-framework metal-containing aluminosilicate zeolite involves the steps of: (a) forming a reactant mixture A comprising (i) an aqueous slurry of an aluminosilicate zeolite in a H.sup.+-form, and (ii) a metal containing compound or free metal, wherein the mixture does not comprise ammonia, ammonium hydroxide or an ammonium salt, and (b) reacting the metal containing compound or free metal with the aluminosilicate zeolite in a H.sup.+-form in reactant mixture A and forming a product mixture B, a reaction mixture comprising the extra-framework metal-containing aluminosilicate zeolite. The metal comprises one or more of copper, iron, manganese, nickel and palladium. The step of reacting the metal with the aluminosilicate zeolite in a H.sup.+-form is performed in a single exchange. The extra-framework metal-containing aluminosilicate zeolite can then be used directly in forming a washcoat that can be applied to a support.

A process for the preparation of an extra-framework metal-containing aluminosilicate zeolite involves the steps of: (a) forming a reactant mixture A comprising (i) an aqueous slurry of an aluminosilicate zeolite in a H.sup.+-form, and (ii) a metal containing compound or free metal, wherein the mixture does not comprise ammonia, ammonium hydroxide or an ammonium salt, and (b) reacting the metal containing compound or free metal with the aluminosilicate zeolite in a H.sup.+-form in reactant mixture A and forming a product mixture B, a reaction mixture comprising the extra-framework metal-containing aluminosilicate zeolite. The metal comprises one or more of copper, iron, manganese, nickel and palladium. The step of reacting the metal with the aluminosilicate zeolite in a H.sup.+-form is performed in a single exchange. The extra-framework metal-containing aluminosilicate zeolite can then be used directly in forming a washcoat that can be applied to a support.

A system for treatment of an exhaust gas stream from an engine is provided, containing an upstream selective catalytic reduction (SCR) catalyst, which receives the exhaust gas stream without any intervening catalyst, a diesel oxidation catalyst (DOC) positioned downstream thereof; a catalyzed soot filter (CSF) downstream of the diesel oxidation catalyst; a second SCR catalyst positioned downstream of the catalyzed soot filter; and an ammonia oxidation (AMOx) catalyst. The application also describes use of such systems to reduce nitrogen oxides (NOx) and hydrocarbons (HC) in an exhaust gas stream.