MWW molecular sieve, preparation method thereof and application of alkaloid in preparation of MWW molecular sieve

Abstract

The invention provides an MWW molecular sieve, a preparation method thereof and application of alkaloid in preparation of the MWW molecular sieve. The alkaloid is applied as a template agent in preparation of the MWW molecular sieve. The preparation method of the MWW molecular sieve comprises the following steps: mixing a silicon source, an aluminum source, an alkali source, a template agent and water according to a molar ratio of 1SiO2: 0.001-0.1 Al2O3: 0.005-0.6 OH <->: 5-50 H2O: 0.01-1 template agent to form a mixture; wherein alkaloid is selected as the template agent; adding an active seed crystal into the mixture to obtain mixed glue; wherein the mass ratio of the active seed crystal to the silicon source is that the mass ratio of the active seed crystal to SiO2 is (0.001-0.2): 1; and carrying out hydrothermal crystallization on the mixed glue at 100-180 DEG C for 24-240 hours to obtain the MWW molecular sieve.

Description

technical field [0001] The invention belongs to the technical field of chemical synthesis, and in particular relates to a MWW molecular sieve, a preparation method thereof and the application of alkaloids in the preparation of the MWW molecular sieve. Background technique [0002] As we all know, molecular sieves such as MCM-22, MCM-49 and MCM-56 are important family members of MWW series molecular sieve structures. The structure of the MWW molecular sieve consists of a ten-membered ring sinusoidal channel (0.40nm×0.59nm) and a semi-supercage (0.70nm×0.71nm×0.71nm) located on the outer surface of the crystal, and also contains a part of the supercage (0.71nm×0.71nm×1.82 nm) composition. Unlike MCM-22 and MCM-49 molecular sieves, the layers of MCM-56 molecular sieves lack supercage connections, and the layers are stacked face to face. MCM-56 molecular sieve is recognized as the intermediate transition state in the synthesis process of MCM-49 molecular sieve, so the synthesi...

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Problems solved by technology

[0005] In summary, in view of the fact that hexamethyleneimine, piperidine and other easily toxic or highly polluting chemicals must be used as templates and additives in the process of preparing MWW series molecular sieves in the prior art, it is necessary to stabilize the structure of synthetic MWW series molecular sieves. However, the process of preparing molecular sieves will cause great harm to the environment and people's health in the process of industrial application, and its industrial application is currently subject to great restrictions.

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