A kind of phosphorus-containing imf structure molecular sieve and preparation method thereof

Abstract

The invention discloses a phosphorus-containing IMF structure molecular sieve and a preparation method thereof, wherein the Al distribution parameter D of the molecular sieve is more than or equal to0.6 and is less than or equal to 0.85, the volume of the mesopores of the molecular sieve accounts for 50-80% of the total pore volume, the volume of the mesopores with the pore size of 2-20 nm accounts for more than 85% of the total mesopore volume, the amount of the strong acid of the molecular sieve accounts for 50-80% of the total acid amount, a ratio of the acid B to the acid L is 7-30, and the phosphorus content (calculated as P2O5) of the molecular sieve is 0.1-15 wt% by using the dry base weight of the molecular sieve as the reference. According to the present invention, the phosphorus-containing IMF structure molecular sieve has advantages of high propylene yield, good propylene selectivity, high ethylene yield and high BTX yield in the catalytic cracking reaction of petroleum hydrocarbons.

Description

technical field [0001] The invention relates to a phosphorus-containing IMF structure molecular sieve and a preparation method thereof. Background technique [0002] For a long time, ethylene, propylene and butene have been the basic organic chemical raw materials for synthetic resin, synthetic fiber and synthetic rubber, among which propylene is an important raw material for the manufacture of petrochemical products after ethylene. At present, the largest source of propylene at home and abroad is the main by-product of thermal cracking to produce ethylene. The second largest source of propylene is almost all from FCC units, which provide about 30% of the demand. In the United States, FCC units provide petrochemical products for propylene. About half of the demand. [0003] Due to the rapidly growing demand for polypropylene, the demand for propylene in the petrochemical industry is faster than that for ethylene, and the construction of ethylene plants is limited by the dem...

AI Technical Summary

Problems solved by technology

[0005] Although IM-5 molecular sieve can have high alkane cracking ability, it is the same as other ten-membered ring molecular sieves. Due to its narrow pore structure, it is difficult for larger reactant molecules such as polycyclic hydrocarbons to enter the crystal pore for reaction, reducing the The effective reaction area of ​​the molecular sieve reduces the reactivity of the molecular sieve; on the other hand, larger product molecules such as isoparaffins and aromatics are not easy to diffuse out of the pores of the molecular sieve, which causes secondary reactions such as excessive hydrogen transfer and coking, which lead to Molecular sieve deactivation, reduced reaction selectivity