Provided is at least one of a CHA-type zeolite having a greater amount of a paired aluminum structure than do CHA-type zeolites of the related art; a catalyst containing the CHA-type zeolite; and a method for producing these. A method for producing a CHA-type zeolite includes crystallizing a composition that contains an alumina source, a silica-alumina source, an alkali source, an organic structure-directing agent and water. Preferably, the composition is prepared by mixing the alumina source, the alkali source, the organic structure-directing agent and the water together and subsequently mixing the silica-alumina source therewith.

Provided is at least one of a CHA-type zeolite having a greater amount of a paired aluminum structure than do CHA-type zeolites of the related art; a catalyst containing the CHA-type zeolite; and a method for producing these. A method for producing a CHA-type zeolite includes crystallizing a composition that contains an alumina source, a silica-alumina source, an alkali source, an organic structure-directing agent and water. Preferably, the composition is prepared by mixing the alumina source, the alkali source, the organic structure-directing agent and the water together and subsequently mixing the silica-alumina source therewith.

The structured catalyst for oxidation for exhaust gas purification includes a support having a porous structure constituted by a zeolite-type compound, and at least one type of oxidation catalyst that is present in the support and selected from the group consisting of metal and metal oxide, the support having channels that communicate with each other, and the oxidation catalyst being present in at least the channels of the support.

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, a gallium content of about 0.1% to about 2.5% by weight on the basis of gallium oxide, and a zirconium content of about 0.1% to about 2.5% by weight on the basis of zirconia; and 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 to the total pore volume of about 20% to about 40%.

A modified Y-type molecular sieve has a rare earth content of about 4-11% by weight on the basis of rare earth oxide, a sodium content of no more than about 0.5 wt % by weight on the basis of sodium oxide, a zinc content of about 0.5-5% by weight on the basis of zinc oxide, a phosphorus content of about 0.05-10% by weight on the basis of phosphorus pentoxide, a framework silica-alumina ratio of about 7-14 calculated on the basis of SiO.sub.2/Al.sub.2O.sub.3 molar ratio, a percentage of non-framework aluminum content to the total aluminum content of no more than about 10%, and a percentage of the pore volume of secondary pores having a pore size of 2-100 nm to the total pore volume of about 20-40%. The modified Y-type molecular sieve has a high crystallinity and a high thermal and hydrothermal stability, and is rich in secondary pores.

The present disclosure provides methods of synthesizing a zeolite with a silica-to-alumina ratio (SAR) of 10 or greater comprising, e.g.: forming a reaction mixture including at least one alumina source, at least one silica source, and at least one organic structure directing agent, wherein the reaction mixture has a solids content of about 10% or greater, and crystallizing the reaction mixture at a temperature of 100° C. or less at atmospheric pressure to form a zeolite.

A phosphorus-containing molecular sieve has a phosphorus content of about 0.3-5 wt %, a pore volume of about 0.2-0.95 ml/g, and a ratio of B acid content to L acid content of about 2-10. The molecular sieve has a specific combination of characteristics, including a high ratio of B acid content to L acid content, thereby exhibiting higher hydrocracking activity and ring-opening selectivity when used in the preparation of a hydrocracking catalyst.

A phosphorus-containing molecular sieve has a phosphorus content of about 0.3-5 wt %, a pore volume of about 0.2-0.95 ml/g, and a ratio of B acid content to L acid content of about 2-10. The molecular sieve has a specific combination of characteristics, including a high ratio of B acid content to L acid content, thereby exhibiting higher hydrocracking activity and ring-opening selectivity when used in the preparation of a hydrocracking catalyst.

A method for producing light aromatics, includes the steps of: i) contacting a feedstock comprising heavy aromatic(s) with a catalyst in a fluidized reactor for aromatics lightening reaction in the presence of hydrogen to obtain a product rich in C6-C8 light aromatic(s) and a spent catalyst, wherein the heavy aromatic is one or more selected from C9+ aromatics; ii) separating the resulted product rich in C6-C8 light aromatic(s) to obtain hydrogen, a non-aromatic component, C6-C8 light aromatic(s) and a C9+ aromatic component; and iii) recycling at least a part of the C9+ aromatic component to the fluidized reactor. The method has strong adaptability to feedstocks and high flexibility in operation and allows a long-period stable operation. The method can produce high-value light aromatics from heavy aromatics that are difficult to be treated and utilized.

A NaY molecular sieve with an aluminum-rich surface is prepared using a process that includes the steps of: a. mixing a directing agent and a first silicon source to obtain a first mixture, wherein the directing agent has a molar composition of Na.sub.2O:Al.sub.2O.sub.3:SiO.sub.2:H.sub.2O=(6-25):1:(6-25):(200-400); b. mixing the first mixture obtained in the step a with a second silicon source, an aluminum source and water to obtain a second mixture; c. carrying out hydrothermal crystallization on the second mixture obtained in the step b, and collecting a solid product. Calculated as SiO.sub.2, the weight ratio of the first silicon source to the second silicon source is 1:(0.01-12). The NaY molecular sieve has larger aluminum distribution gradient from the surface to the center of the particle than the conventional molecular sieve.