Preparation method of high-silicon ZSM-5 molecular sieve with mesoporous structure

Abstract

The embodiment of the invention provides a preparation method of a high-silicon ZSM-5 molecular sieve with a mesoporous structure, and belongs to the technical field of molecular sieve preparation. The preparation method comprises the following steps: dissolving tetrapropylammonium bromide in water, gradually adding a silicon source at a certain temperature, placing the mixture in an ultrasonic device for ultrasonic treatment for 2-3 hours, and filtering to obtain a pure silicon ZSM-5 crystal cluster; the preparation method comprises the following steps: fully mixing an organic pore-enlarging agent, an inorganic pore-enlarging agent, ZSM-5 crystal clusters and water, adding sodium hydroxide to adjust the pH value to 9-11, simultaneously adding an aluminum source and a silicon source in a stirring state, and stirring for a period of time at a certain temperature; filling the crystallization liquid into a crystallization kettle, crystallizing for a certain time at a certain temperature, filtering, washing, drying and roasting to obtain the high-silicon ZSM-5 molecular sieve. The microporous molecular sieve is subjected to chambering modification and the hydrophobic property of the molecular sieve is improved, so that the adsorption capacity of the molecular sieve on macromolecular organic matters is improved.

Description

technical field [0001] The invention relates to the technical field of molecular sieve preparation, in particular to a preparation method of a high-silicon ZSM-5 molecular sieve with a mesoporous structure. Background technique [0002] At present, ZSM-5 molecular sieves have been widely used in the field of VOCs (Volatile Organic Compounds; volatile organic compounds) adsorption. However, as a kind of microporous molecular sieve with MFI topology, ZSM-5 molecular sieve has limited application in the adsorption of macromolecular organic substances. For macromolecular organics whose molecular size exceeds the pore size of zeolite, molecular sieves are powerless. At the same time, industrial VOCs contain a large amount of water vapor. Due to the weak hydrophobicity of molecular sieves, there will be competition between water vapor and molecular sieves when adsorbing macromolecular organic substances, which further causes the adsorption capacity of molecular sieves to deterior...

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Problems solved by technology

At the same time, industrial VOCs contain a large amount of water vapor. Due to the weak hydrophobicity of molecular sieves, there will be competition between water vapor and molecular sieves when adsorbing macromolecular organics, which will further cause the adsorption capacity of molecular sieves to deteriorate.