A kind of molecular sieve with multi-level pores and wide silicon-aluminum ratio euo structure and its synthesis method

Abstract

The invention discloses a EUO (Europium Oxide) structural molecular sieve with hierarchical pores and wide silica-alumina ratio and a synthetic method. The synthetic method comprises the following steps: performing crystallization synthesis by taking a long-chain silane compound as a crystallization assistant, taking double quaternary ammonium salt with an alkane structure being substituted by a double quinary heterocyclic group as an organic template, and heating silica-aluminum sol to a target temperature at the rate of 2 to 20 DEG C / h, wherein the target crystallization synthesis temperature is 150 to 200 DEG C; then performing separation, washing, drying and roasting to remove the organic template in order to obtain EUO structural molecular sieve raw powder with hierarchical pores andwide silica-alumina ratio, and performing ammonium ion exchange, drying and roasting in sequence to obtain an H-type EUO structural molecular sieve with hierarchical pores and wide silica-alumina ratio. The zeolite molecular sieve provided by the invention has the advantages of hierarchical pore structure, wide silica-alumina ratio range, small grain size, high relative crystallinity and high hydrothermal stability. Reaction evaluation shows high isomerization activity and selectivity of xylene, so that the EUO structural molecular sieve has a very good industrial application prospect.

Description

technical field [0001] The invention relates to a molecular sieve with multi-level pores and a wide silicon-aluminum ratio EUO structure and a synthesis method, 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 m...

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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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