Phosphorus-containing ZSM-5 molecular sieve, preparation method and applications thereof

Abstract

The invention relates to a phosphorus-containing ZSM-5 molecular sieve, which is characterized in that only a phosphorus shape characteristic peak exists in the 31P MAS-NMR spectrum of the molecular sieve, and the chemical shift of the characteristic peak is at -30.0+ / -2 ppm. According to the present invention, a ZSM-5 molecular sieve and boron phosphate are mixed to make the phosphorus loading capacity of the ZSM-5 molecular sieve at least be 0.1 wt% (calculated as P2O5), and drying and calcining are performed to obtain the phosphorus-containing ZSM-5 molecular sieve.

Description

technical field [0001] The present invention relates to a phosphorus-containing ZSM-5 molecular sieve, its preparation method and application, and more specifically relates to a modified phosphorus-containing ZSM-5 molecular sieve, its preparation method and application. Background technique [0002] ZSM-5 molecular sieve is a medium-pore molecular sieve (USP 3702886) with a high-silicon three-dimensional straight channel developed by the Mobil Petroleum Company of the United States. It has a unique pore structure and has good shape-selective catalysis and isomerization Chemical properties, high thermal and hydrothermal stability, high specific surface area, wide range of silicon-aluminum ratio variation, unique surface acidity and low carbon formation, are widely used as catalysts and catalyst supports, and successfully used in alkylation , Isomerization, disproportionation, catalytic cracking, methanol to gasoline, methanol to olefins and other production processes. [00...

AI Technical Summary

Problems solved by technology

Although HZSM-5 molecular sieve has good shape-selective properties and isomerization properties, it has good hydrothermal structural stability under the harsh high-temperature hydrothermal conditions of FCC, but its disadvantage is that it is prone to skeleton dealumination. The retention of the acid center is significantly reduced, the stability of the hydrothermal activity is poor, and the molecular sieve is irreversibly deactivated

In the disclosed method of CN85102828, phosphorus-containing compounds include phosphorus-containing compounds, such as trimethyl phosphate, triphenylphosphine, etc., and inorganic phosphides, such as phosphoric acid, ammonium phosphate, etc. 2 o 5 At 6-12wt%, it is easy to block the pores, cover the medium-strong B acid center, and reduce its catalytic performance

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