Method for synthesizing mobil composition of matters-41(MCM-41) mesoporous molecular sieve

Abstract

The invention relates to a method for synthesizing a mobil composition of matters-41(MCM-41) mesoporous molecular sieve. The method comprises the following steps of: dissolving SiO2 filter cakes obtained by recovering MCM-48 synthetic mother liquor in an alkali solution, and stirring at constant temperature of 60 DEG C for 1 hour; dripping the solution into an aqueous solution containing a surfactant, stirring at the constant temperature of 60 DEG C for 2 hours, cooling to the room temperature, transferring the mixture to a closed reactor, and crystallizing at the temperature of between 80 and 130 DEG C for 15 to 24 hours; and filtering, washing and drying a crystallized product to obtain the MCM-41 mesoporous molecular sieve, wherein a molar ratio of SiO2 to cetyltrimethylammonium tosylate (CTATos) to NaOH or KOH to H2O in the MCM-41 mesoporous molecular sieve is 1:(0.015-0.06):(0.15-0.35):(40-200). Compared with the prior art, the method has the obvious advantages that: a silicon source which is left in the synthetic mother liquor of a mesoporous material can be recycled, the using amount of the surfactant is low, the utilization rate of the silicon source is high, and the quality and purity of products are high; and in addition, and the method is short in synthetic period, low in cost and high in repeatability, the products are easy to synthesize on a large scale, so the method is an environment-friendly synthetic process.

Description

technical field [0001] The invention relates to a preparation method of mesoporous molecular sieve, in particular to a preparation method of silicon-based mesoporous molecular sieve MCM-41 with high hydrothermal stability at extremely low cost. Background technique [0002] Ordered mesoporous materials refer to mesoporous materials with regular and ordered channels. The synthesis of mesoporous materials began as early as 1971. Before 1990, Kuroda in Japan had also used layered silicate in the surface activity. The synthesis of mesoporous materials began with the transformation in the presence of an agent. The report by Mobil in 1992 attracted widespread attention and was considered to be the real beginning of the synthesis of mesoporous materials. Mobil used surfactants as templates to synthesize the M41S series of mesoporous materials, including MCM-41 (hexagonal phase), MCM-48 (cubic phase) and MCM-50 (layered structure). Since the material has a regular pore structure an...

AI Technical Summary

Problems solved by technology

Although this material has many advantages such as simple synthesis method, easy repeatability, and easy recovery of products, due to the high alkalinity of the synthesis system and the low utilization rate of silicon sources (70% loss of silicon species), the synthesis yield of MCM-48 reduce

In addition, during the large-scale production of mesoporous materials (2L reactor), the direct discharge of waste liquid containing silicon species and fluorine ions is likely to cause environmental pollution

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