A catalyst composition for selective catalytic reduction of NO.sub.x by ammonia or compounds, such as urea, generating ammonia under exhaust gas conditions. The composition includes a) a copper ion exchanged zeolite particles having a Si/Al.sub.2 molar ratio (SAR) of 15 or less and a copper content sufficiently high to perform the catalytic reduction, b) a nanocrystalline aluminium compound in an amount sufficient for stabilizing the zeolite, and c) a zirconium compound in an amount sufficient to improve hydrothermal durability of the catalyst composition.

A modified Y-type molecular sieve has a rare earth content of about 4% to about 11% by weight on the basis of the oxide, a phosphorus content of about 0.05% to about 10% by weight on the basis of P.sub.2O.sub.5, a sodium content of no more than about 0.5% by weight on the basis of sodium oxide, and an active element content of about 0.1% to about 5% by weight on the basis of the oxide, with the active element being gallium and/or boron. The modified Y-type molecular sieve has a total pore volume of about 0.36 mL/g to about 0.48 mL/g, a percentage of the pore volume of secondary pores having a pore size of 2-100 nm of about 20% to about 40%; a lattice constant of about 2.440 nm to about 2.455 nm, and a lattice collapse temperature of not lower than about 1060° C.

Methods and phosphorus-containing solid catalysts for catalyzing dehydration of cyclic ethers (e.g., furans, such as 2,5-dimethylfuran) and alcohols (e.g., ethanol and isopropanol). The alcohols and cyclic ethers may be derived from biomass. One example includes a tandem Diels-Alder cycloaddition and dehydration of biomass-derived 2,5-dimethyl-furan and ethylene to renewable p-xylene. The phosphorus-containing solid catalysts are also active and selective for dehydration of alcohols to alkenes.

The present disclosure provides a method of preparing a catalyst for synthesizing dimethyl ether or methylacetate from synthetic gas that includes preparing a nanosheet ferrierite zeolite (FER), and co-precipitating the nanosheet ferrierite zeolite and a precursor of a Cu—Zn—Al-based oxide (CZA) to obtain a hybrid CZA/FER catalyst.

Molecular sieves comprising intergrowths of cha and aft having an “sfw-GME tail”, at least one structure directing agent (SDA) within the framework of the molecular sieve, an intergrowth of CHA and GME framework structures, cha cavities, and aft cavities are described. A first SDA comprising either an N,N-dimethyl-3,5-dimethylpiperidinium cation or a N,N-diethyl-2,6-dimethylpiperidinium cation is required. A second SDA, which can further be present, is a CHA or an SFW generating cation. The amount of the second SDA-2 used can change the proportion of the components in the cha-aft-“sfw-GME tail”. Activated molecular sieves formed from SDA containing molecular sieves are also described. Compositions for preparing these molecular sieves are described. Methods of preparing a SDA containing JMZ-11, an activated JMZ-11, and metal containing activated JMZ-11 are described. Methods of using activated JMZ-11 and metal containing activated JMZ-11 in a variety of processes, such as treating exhaust gases and converting methanol to olefins are described.

A method of preparing a catalyst for synthesizing dimethyl ether from synthetic gas includes preparing a mesoporous ferrierite zeolite (FER), and co-precipitating a precursor of a mesoporous ferrierite zeolite and a Cu—Zn—Al-based oxide (CZA) to obtain a hybrid CZA/mesoFER catalyst.

A passive NOx absorber for treating an exhaust gas from a diesel engine is described. The passive NOx absorber comprises a first washcoat region comprising a zeolite catalyst, the zeolite catalyst comprising a noble metal and a zeolite having a SAR of 2-15.

A method of converting nitrogen oxides in a gas to nitrogen by contacting the nitrogen oxides with a nitrogenous reducing agent in the presence of a zeolite catalyst containing at least one transition metal, wherein the zeolite is a small pore zeolite containing a maximum ring size of eight tetrahedral atoms, wherein the at least one transition metal is selected from the group consisting of Cr, Mn, Fe, Co, Ce, Ni, Cu, Zn, Ga, Mo, Ru, Rh, Pd, Ag, In, Sn, Re, Ir and Pt.

Methods for cracking a hydrocarbon feed stream include contacting a hydrocarbon feed stream with a catalyst system in a catalytic cracking unit having a flowing gas stream to obtain a cracking product containing light olefins. The catalyst system includes at least a base catalyst. The base catalyst includes a pentasil zeolite. The pentasil zeolite includes from 0.01% to 5% by mass lithium atoms, as calculated on an oxide basis, based on the total mass of the pentasil zeolite. The flowing gas stream comprises hydrogen and, optionally, at least one additional carrier gas.

The present disclosure relates to a method for forming a catalyst article comprising: (a) forming a plastic mixture having a solids content of greater than 50 % by weight by mixing together a crystalline small pore molecular sieve in an H.sup.+ or NH.sub.4.sup.+ form, iron sulphate, an inorganic matrix component, an organic auxiliary agent, an aqueous solvent and optionally inorganic fibres; (b) moulding the plastic mixture into a shaped article; and (c) calcining the shaped article to form a solid catalyst body. The present disclosure further relates to a catalyst article, an exhaust system, and a method of treating an exhaust gas.