A kind of molecular sieve with hierarchical hole euo structure and its synthetic method

Abstract

The invention discloses a hierarchical-pore EUO structure molecular sieve and a synthesis method thereof. The synthesis method comprises the following steps: crystallizing and synthesizing an silicon-aluminium solution by raising to target temperature at the heating rate of 2-20 DEG C / h by taking a long-chain silane compound as a crystallization assistant and biquaternary ammonium salt of a bi-hexa-heterocycle group substituted alkane structure as an organic template agent, wherein the target crystallizing and synthesizing temperature is 150-190 DEG C; then separating, washing, drying and roasting to remove the organic template agent to obtain a hierarchical-pore EUO structure molecular sieve material; and then sequentially performing ammonium exchange, drying and roasting to obtain the H-type hierarchical-pore EUO structure molecular sieve. The zeolite molecular sieve provided by the invention has a hierarchical-pore structure, and is wide in product silicon-aluminium ratio, small ingrain size and high in relative crystallinity, and strong in hydrothermal stability; reaction assessment shows good xylene isomerization activity and selectivity, and therefore, the hierarchical-poreEUO structure molecular sieve has good industrial application prospect.

Description

technical field [0001] The invention relates to a molecular sieve with a multi-level hole EUO structure and a synthesis method thereof, belonging to the field of inorganic material synthesis. Background technique [0002] In the crystal structure of the EUO topological structure molecular sieve, there is a one-dimensional ten-membered ring 0.54nm×0.41nm channel in the [100] direction, and there are 0.81nm deep twelve-membered ring 0.68nm×0.58nm side pockets on both sides of the ten-membered ring channel. . EU-1, ZSM-50 and TPZ-3 molecular sieves all have EUO topology, among which EU-1 molecular sieve is a molecular sieve that has been widely studied in recent years. The bifunctional catalyst prepared by the acidic component of the structure catalyst shows good activity and selectivity in the catalytic reaction of C8 aromatics hydroisomerization and benzene isopropylation, and is known as a new generation of xylene isomerization preferred catalyst material. [0003] US4537...

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Problems solved by technology

[0004] The EUO structure molecular sieve preparation methods disclosed in the above documents mainly include traditional hydrothermal method and solid-phase in-situ method, but the molecular sieve structure is basically the same, its particle size is generally large, all in the micron level, and miscellaneous crystals are prone to appear. The lifespan is severely limited, and the product yield needs to be improved

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