Provided are a hierarchical porous ZSM-5 molecular sieve and a preparation method therefor. The molecular sieve comprises micropores and mesopores, wherein the pore size of the micropores is 0.5-1.8 nm, the pore size of the mesopores is 4-30 nm, and the particle size is 0.3-4 μm. The molecular sieve is prepared by using a hemicellulose as a hard template agent. Also provided are a hierarchical porous HZSM-5 molecular sieve, which is obtained by subjecting the ZSM-5 molecular sieve to ion exchange with an ammonium chloride solution, and the use of ZSM-5 and HZSM-5 molecular sieves in the preparation of a sound-absorbing material, the sound-absorbing material made from the molecular sieve, and a speaker loaded with the sound-absorbing material. After being prepared into sound-absorbing particles, the molecular sieve can more effectively improve the absorption and desorption performances of air molecules, improve the low-frequency response of a speaker, improve the acoustic performance of the speaker, and improve the acoustic improvement stability of sound-absorbing particles in the speaker.

Provided are a hierarchical porous ZSM-5 molecular sieve and a preparation method therefor. The molecular sieve comprises micropores and mesopores, wherein the pore size of the micropores is 0.5-1.8 nm, the pore size of the mesopores is 4-30 nm, and the particle size is 0.3-4 μm. The molecular sieve is prepared by using a hemicellulose as a hard template agent. Also provided are a hierarchical porous HZSM-5 molecular sieve, which is obtained by subjecting the ZSM-5 molecular sieve to ion exchange with an ammonium chloride solution, and the use of ZSM-5 and HZSM-5 molecular sieves in the preparation of a sound-absorbing material, the sound-absorbing material made from the molecular sieve, and a speaker loaded with the sound-absorbing material. After being prepared into sound-absorbing particles, the molecular sieve can more effectively improve the absorption and desorption performances of air molecules, improve the low-frequency response of a speaker, improve the acoustic performance of the speaker, and improve the acoustic improvement stability of sound-absorbing particles in the speaker.

Disclosed herein are modified zeolites and methods for making modified zeolites. In one or more embodiments disclosed herein, a modified zeolite may include a microporous framework including a plurality of micropores having diameters of less than or equal to 2 nm. The microporous framework includes at least silicon atoms and oxygen atoms. The modified zeolite may further include organometallic moieties each bonded to bridging oxygen atoms. The organometallic moieties include a hafnium atom. The hafnium atom is bonded to a bridging oxygen atom, and bridging oxygen atom bridges the hafnium atom of the organometallic moiety and a silicon atom of the microporous framework.

Disclosed herein are modified zeolites and methods for making modified zeolites. In one or more embodiments disclosed herein, a modified zeolite may include a microporous framework including a plurality of micropores having diameters of less than or equal to 2 nm. The microporous framework includes at least silicon atoms and oxygen atoms. The modified zeolite may further include organometallic moieties each bonded to bridging oxygen atoms. The organometallic moieties include a hafnium atom. The hafnium atom is bonded to a bridging oxygen atom, and bridging oxygen atom bridges the hafnium atom of the organometallic moiety and a silicon atom of the microporous framework.

The present invention relates to a specific continuous process for preparing a zeolitic material having a framework structure type selected from the group consisting of MFI, MEL, IMF, SVY, FER, SVR, and intergrowth structures of two or more thereof, preferably an MFI- and/or MEL-type framework structure, comprising Si, Ti, and O, and to a zeolitic material as obtainable and/or obtained according to said process. Further, the present invention relates to a process for preparing a molding, and to a molding obtainable and/or obtained according to said process. Yet further, the present invention relates to a use of said zeolitic material and molding.

The invention relates to a method for preparing a hierarchical porous zeolite membrane and an application thereof, comprising the following steps: a mesoporous structure-directing agent is added to limit the growth of zeolite crystals, and self-assembled in the crystallization process to generate a mesoporous structure. Based on a seed crystal induced secondary nucleation mechanism, this method can realize one-step hydrothermal synthesis of hierarchical porous zeolite membrane with the advantages of mild and controllable synthesis conditions, simple process, good repeatability, reduced energy consumption and cost savings. The hierarchical porous zeolite membrane prepared by the method has good cut-off performance, and the cut-off molecular weight is adjustable between 200 to 500,000 Da.

The invention relates to a method for preparing a hierarchical porous zeolite membrane and an application thereof, comprising the following steps: a mesoporous structure-directing agent is added to limit the growth of zeolite crystals, and self-assembled in the crystallization process to generate a mesoporous structure. Based on a seed crystal induced secondary nucleation mechanism, this method can realize one-step hydrothermal synthesis of hierarchical porous zeolite membrane with the advantages of mild and controllable synthesis conditions, simple process, good repeatability, reduced energy consumption and cost savings. The hierarchical porous zeolite membrane prepared by the method has good cut-off performance, and the cut-off molecular weight is adjustable between 200 to 500,000 Da.

An ethylbenzene dealkylation catalyst composition comprising a ZSM-5 type zeolite as a carrier component, wherein said zeolite has been synthesized from an aqueous reaction mixture comprising one or more alumina sources, one or more silica sources, one or more alkali sources, and one or more primary and/or secondary amines and wherein the ZSM-5 type zeolite has a number average crystallite size in the range of from 1 to 10 μm and a molar silica-to-alumina ratio (SAR) in the range of from 30 to 70; a method for reducing xylene losses in an ethylbenzene dealkylation process, said method comprising conducting the ethylbenzene dealklylation process in the presence of the afore-mentioned catalyst composition; and a process for the dealkylation of ethylbenzene, which process comprises contacting, in the presence of hydrogen, a feedstock which comprises ethylbenzene with said catalyst composition.

Disclosed herein are modified zeolites and methods for making modified zeolites. In one or more embodiments disclosed herein, a modified zeolite may include a microporous framework comprising a plurality of micropores having diameters of less than or equal to 2 nm. The microporous framework may include at least silicon atoms and oxygen atoms. The modified zeolite may further include organometallic moieties each bonded to bridging oxygen atoms. The organometallic moieties may include a titanium atom. The titanium atom may be bonded to a bridging oxygen atom, and the bridging oxygen atom may bridge the titanium atom of the organometallic moiety and a silicon atom of the microporous framework.

Disclosed herein are modified zeolites and methods for making modified zeolites. In one or more embodiments disclosed herein, a modified zeolite may include a microporous framework comprising a plurality of micropores having diameters of less than or equal to 2 nm. The microporous framework may include at least silicon atoms and oxygen atoms. The modified zeolite may further include organometallic moieties each bonded to bridging oxygen atoms. The organometallic moieties may include a titanium atom. The titanium atom may be bonded to a bridging oxygen atom, and the bridging oxygen atom may bridge the titanium atom of the organometallic moiety and a silicon atom of the microporous framework.