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.

The present invention relates to a catalyst comprising a carrier substrate of the length L, a passive nitrogen oxide adsorber and means to control the temperature of the carrier substrate, as well as a process for cleaning of an exhaust gas emitted from a lean burn engine.

Provided is a catalyst washcoat comprising (i) a molecular sieve loaded with about 1 to about 10 weight percent of at least non-aluminum promoter metal (wherein the promoter metal weight percent is based on the weight of the molecular sieve); and (ii) about 1 to about 30 weight percent of a binder having a d90 particle size of less than 10 microns (wherein the binder weight percent is based on the total weight of the washcoat). In another aspect of the invention, the catalyst washcoat is applied to a wall-flow filter to form a catalyst article. In another aspect of the invention the catalyst article is part of an exhaust gas treatment system. And in yet another aspect of the invention, provided is a method for treating exhaust gas using the catalyst article.

Provided is a catalyst washcoat comprising (i) a molecular sieve loaded with about 1 to about 10 weight percent of at least non-aluminum promoter metal (wherein the promoter metal weight percent is based on the weight of the molecular sieve); and (ii) about 1 to about 30 weight percent of a binder having a d90 particle size of less than 10 microns (wherein the binder weight percent is based on the total weight of the washcoat). In another aspect of the invention, the catalyst washcoat is applied to a wall-flow filter to form a catalyst article. In another aspect of the invention the catalyst article is part of an exhaust gas treatment system. And in yet another aspect of the invention, provided is a method for treating exhaust gas using the catalyst article.

Embodiments of zeolite composite catalysts and methods of producing the zeolite composite catalysts are provided, where the methods comprise dissolving in an alkaline solution a catalyst precursor comprising at least one mesoporous zeolite while heating, stirring, or both to yield a dissolved zeolite solution, where the mesoporous zeolite has a molar ratio of SiO.sub.2/Al.sub.2O.sub.3 of at least 30, where the mesoporous zeolite comprises zeolite beta, adjusting the pH of the dissolved zeolite solution, aging the pH adjusted dissolved zeolite solution to yield solid zeolite composite from the dissolved zeolite solution, and calcining the solid zeolite composite to produce the zeolite composite catalyst, where the zeolite composite catalyst has a mesostructure comprising at least one disordered mesophase and at least one ordered mesophase, and where the zeolite composite catalyst has a surface area defined by the Brunauer-Emmett-Teller (BET) analysis of at least 600 m.sup.2/g.

Methods are provided for activation of catalysts comprising low amounts of a hydrogenation metal, such as low amounts of a Group 8-10 noble metal. The amount of hydrogenation metal on the catalyst can correspond to 0.5 wt % or less (with respect to the weight of the catalyst), or 0.1 wt % or less, or 0.05 wt % or less. Prior to loading a catalyst into a reactor, the corresponding catalyst precursor can be first activated in a hydrogen-containing atmosphere containing 1.0 vppm of CO or less. The thus first-activated catalyst can be transferred to a reactor with optional exposure to oxygen during the transfer, where it can be further activated using a hydrogen-containing atmosphere containing 3.0 vppm of CO or higher, to yield a twice-activated catalyst with high performance. The catalyst can be advantageously a transalkylation catalyst or an isomerization catalyst useful for converting aromatic hydrocarbons.

The main object of the present invention is to provide a new method for preparing the copper-containing silicoaluminate form of the AEI zeolite structure by means of a direct synthesis methodology. This new process involves combining a organometallic copper-complex with an additional organic molecule capable of directing the crystallisation of the silicoaluminate form of the AEI zeolite structure as organic structure-directing agents (OSDAs).

The present disclosure relates to processes for formation of a molecular sieve, particularly a metal-promoted molecular sieve, and more particularly an Iron(III) exchanged zeolite. Preferably, the zeolite is of the chabazite form or similar structure. The processes can include combining a zeolite with Iron(III) cations in an aqueous medium. The process can be carried out at a pH of less than about 7, and a buffering material can be used with the aqueous medium. The processes beneficially result in Iron exchange that can approach 100% along with removal of cations (such as sodium, NH4, and H) from the zeolite. An Iron(III)-exchanged zeolite prepared according to the disclosed processes can include about 2,000 ppm or less of cation and about 1% by weight or greater of Iron(III). The disclosure also provides catalysts (e.g., SCR catalysts) and exhaust treatment systems including the Iron(III)-exchanged zeolite.

The invention relates to a catalyst composition comprising a) a carrier comprising: (i) of from 5 to 95 wt % of CON type zeolite, (ii) of from 5 to 95 wt % of ZSM-5 type zeolite; and (iii) of from 10 to 60 wt % of inorganic binder; and b) of from 0.001 to 10 wt % one or more metals selected from the group consisting of Group 6-11 of the IUPAC Periodic Table of Elements. The invention further relates to a process for preparing the catalyst composition and to a process for the conversion of an alkylaromatic hydrocarbons containing feedstock using a catalyst prepared by the present process.

The invention relates to a catalyst composition comprising a) a carrier comprising: (i) of from 5 to 95 wt % of CON type zeolite, (ii) of from 5 to 95 wt % of ZSM-5 type zeolite; and (iii) of from 10 to 60 wt % of inorganic binder; and b) of from 0.001 to 10 wt % one or more metals selected from the group consisting of Group 6-11 of the IUPAC Periodic Table of Elements. The invention further relates to a process for preparing the catalyst composition and to a process for the conversion of an alkylaromatic hydrocarbons containing feedstock using a catalyst prepared by the present process.