Preparation method of H-ZSM (Zeolite Socony Mobil)-20 molecular sieve

Abstract

The invention relates to a preparation method of an H-ZSM (Zeolite Socony Mobil)-20 molecular sieve. The preparation method is characterized in that colloidal liquor is prepared from the following components in a molar ratio that SiO2:Al2O3:NaF:Na2O:15-Crown-5:18-Crown-6:H2O=(2-10):1.0:(0.5-1):(1-2.4):(0.0-0.5):(0.0-0.5):(10-100). The preparation method comprises the following specific steps: dissolving sodium hydroxide, haloid and aluminate in water, and magnetically stirring for 10 minutes to prepare liquor A; dropwise adding 30% silicon dioxide sol slowly into the liquor A, stirring for 30 minutes, then slowly adding a template, continuously stirring for 3 hours to obtain colloidal liquor, and standing for 24 hours at room temperature; transferring the colloidal liquor to a hydro-thermal synthetic reaction kettle, crystallizing for 10-20 days at 100-170 DEG C, cooling, filtering, washing, drying and grinding, heating to 450-600 DEG C through temperature programming and roasting for 3-10 ours to remove the template to obtain the molecular sieve ZSM-20; after ion exchange of the ZSM-20 by 0.1-2.0mol / L of ammonium nitrate liquor for 2-8 hours, repeatedly exchanging for 2-3 time; filtering, washing, drying and roasting to obtain the H-ZSM-20.

Description

technical field [0001] The present invention relates to a preparation method of H-ZSM-20 molecular sieve, more precisely to a kind of ZSM-20 with three-dimensional 12-membered ring reticular intersecting uniform channel, FAU and EMT symbiotic molecular sieve, high activity and thermal stability Molecular sieve preparation method. Background technique [0002] U.S. MobiI Petroleum Company announced in USP3972983 in 1976 the preparation method of ZSM-20 molecular sieve, because it has higher silicon-aluminum ratio, unique pore structure and excellent thermal and hydrothermal structural stability, in the organic compound Applications in catalytic conversion processes have received attention. The synthesis method of ZSM-20 molecular sieve uses the classic organoammonium tetraethylammonium hydroxide as a template agent, the silicon source used in the synthesis is mainly tetraethyl silicate, and the aluminum source is mostly sodium metaaluminate aluminates. [0003] Regarding th...

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Problems solved by technology

[0004] Regarding the research on zeolite molecular sieve ZSM-20, it can be seen that the above-mentioned documents are all early studies, and the research content is limited to the preparation method in the patent USP3972983. This method uses a large amount of template agent, harsh conditions, and poor reproducibility. There are other crystal phases such as Beta and Y appearing

There is no breakthrough in the research on the improvement of the preparation method of ZSM-20, and further research on ZSM-20 has stagnated in recent years

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