Disclosed is a method of preparing a high-performance zeolite catalyst for reducing nitrogen oxide emissions, and more particularly a technique for preparing a zeolite catalyst, suitable for use in effectively removing nitrogen oxide (NOx), among exhaust gases emitted from vehicle internal combustion engines through selective catalytic reduction (SCR), thereby exhibiting high efficiency, high chemical stability and high thermal durability upon SCR using the prepared catalyst.

A method for producing a hierarchical mesoporous beta includes mixing a beta zeolite with an aqueous metal hydroxide solution and heating the beta zeolite and the aqueous metal hydroxide mixture to produce a desilicated beta zeolite, contacting the desilicated beta zeolite with an ammonium salt solution to produce an intermediate hierarchical mesoporous beta zeolite, and treating the intermediate hierarchical mesoporous beta zeolite with an acidic solution to produce the hierarchical mesoporous beta zeolite. The hierarchical mesoporous beta zeolite includes a molar ratio of silicon to aluminum of greater than 12.5, a total pore volume of greater than or equal to the total pore volume of the intermediate hierarchical mesoporous beta zeolite, and an average mesopore size of greater than or equal to the average mesopore size of the hierarchical mesoporous beta zeolite. The method may also include calcining the intermediate hierarchical mesoporous beta zeolite.

Disclosed is a method of preparing a high-performance zeolite catalyst for reducing nitrogen oxide emissions, and more particularly a technique for preparing a zeolite catalyst, suitable for use in effectively removing nitrogen oxide (NOx), among exhaust gases emitted from vehicle internal combustion engines through selective catalytic reduction (SCR), thereby exhibiting high efficiency, high chemical stability and high thermal durability upon SCR using the prepared catalyst.

The present invention further provides a method of making an metal-loaded aluminosilicate zeolite having a maximum pore opening defined by eight tetrahedral atoms from pre-existing aluminosilicate zeolite crystallites, wherein the metal is present in a range of from 0.5 to 5.0 wt. % based on the total weight of the metal-loaded aluminosilicate zeolite.

A method for producing a zeolite with improved Si/Al according to the present invention includes the steps of: subjecting a zeolite synthesized without using an organic structure directing agent to ion exchange, thereby obtaining a sodium-type, a proton-type, or an ammonium-type zeolite; and bringing the zeolite subjected to ion exchange into contact with an ammonium salt solution, thereby dealuminating the zeolite. It is preferable that the ammonium salt is any one of ammonium oxalate, ammonium fluoride, ammonium fluorosilicate, ammonium fluoroborate, ammonium fluorophosphate, ammonium fluorotitanate, and ammonium florozirconate. It is also preferable that the zeolite after ion exchange is exposed to water vapor, and is then brought into contact with the ammonium salt solution.

A method for upgrading pyrolysis oil includes contacting a pyrolysis oil feed with hydrogen in the presence of a mixed metal oxide catalyst in a slurry reactor to produce an intermediate stream comprising light aromatic compounds comprising mono-aromatic compounds, di-aromatic compounds, or both, passing the intermediate stream to a hydrocracking reactor, contacting the intermediate stream with hydrogen in the presence of a hydrocracking catalyst in a hydrocracking reactor to produce a hydrocracking effluent comprising aromatic compounds having six to nine carbon atoms, passing the hydrocracking effluent to a transalkylation reactor, and contacting the hydrocracking effluent with hydrogen in the presence of a transalkylation catalyst in the transalkylation reactor to produce a transalkylation effluent comprising xylenes.

Provided are a molecular sieve catalyst, a preparation method therefor, an application thereof. The molecular sieve catalyst contains a modified Na-MOR molecular sieve, and the modification comprises: organic ammonium salt exchange, dealumination treatment, and ammonium ion exchange. The catalyst obtained by the method is used in dimethyl ether for one-step production of methyl acetate. The catalyst has high activity and stable performance, and the needs of industrial production can be satisfied.

Disdosed is a method of preparing a high-performance zeolite catalyst for reducing nitrogen oxide emissions, and more particularly a technique for preparing a zeolite catalyst, suitable for use in effectively removing nitrogen oxide (NOx), among exhaust gases emitted from vehicle internal combustion engines through selective catalytic reduction (SCR), thereby exhibiting high efficiency, high chemical stability and high thermal durability upon SCR using the prepared catalyst.

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.

An aromatization catalyst and preparation process and use thereof is set forth. The catalyst comprises an inorganic oxide and a modified Ga-ZSM-5 zeolite, which comprises a modified ZSM-5 zeolite with a hierarchical macro-meso-microporosity and gallium deposited in channels of and/or on surfaces of the modified ZSM-5 zeolite. The hierarchical porosity of the modified ZSM-5 zeolite in the catalyst can reduce diffusion resistance of products during the aromatization reaction, thereby retarding carbon depositing rate and substantially improving catalytic activity, aromatic hydrocarbon selectivity, stability and lifetime of the catalyst. When being used in aromatization of propane, the catalyst exhibits a high stability, a lifetime of more than 320 hours, and a selectivity to aromatic hydrocarbons of up to 73.3 wt. %.