Core-shell type molecular sieve containing phosphorus and metal and synthesis method thereof

Abstract

The invention belongs to the technical field of catalytic material synthesis, and relates to a core-shell type molecular sieve containing phosphorus and metal and a synthesis method thereof. The nuclear phase molecular sieve of the core-shell type molecular sieve containing phosphorus and metal is a ZSM-5 molecular sieve, and the shell molecular sieve of the core-shell type molecular sieve containing phosphorus and metal is a beta molecular sieve. In 27Al MAS NMR of the core-shell type molecular sieve containing phosphorus and metal, the ratio of the resonance signal peak area with the chemical shift of 39 +/-3ppm to the resonance signal peak area with the chemical shift of 54 +/-3ppm is (0.01-infinity): 1. The preparation method comprises the step of introducing phosphorus and modified metal into a hydrogen type core-shell molecular sieve. The core-shell molecular sieve containing phosphorus and metal provided by the invention has good catalytic cracking performance.

Description

technical field [0001] The invention belongs to the technical field of catalytic material synthesis, and relates to a phosphorus- and metal-containing core-shell molecular sieve and a synthesis method thereof. Background technique [0002] Zeolite molecular sieves are widely used in petroleum refining and processing, among which ZSM-5 molecular sieve with MFI topology and β molecular sieve with BEA topology are two widely used molecular sieves in industry. ZSM-5 belongs to the orthorhombic crystal system, and the unit cell parameters are The number of Al atoms in the unit cell can vary from 0 to 27, and the ratio of silicon to aluminum can be changed in a wide range; the ZSM-5 framework contains two intersecting 10-membered ring channel systems, in which the channel is curved in an S shape with a pore diameter of The pores are linear, with a diameter of β molecular sieve is the only high silica zeolite with large pores and three-dimensional structure found so far with a...

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Problems solved by technology

[0003] Originally synthesized ZSM-5 molecular sieves and β molecular sieves, in some cases, can not be used directly to obtain ideal application effects, so it needs to be modified for different reactions, for example, in order to make molecular sieves have better catalytic cracking of propylene Selectivity, some studies have introduced metals into ZSM-5 and β molecular sieves for modification, and there are also studies in the prior art that ZSM-5 molecular sieves and β molecular sieves are used in combination to convert hydrocarbon oils

However, the prior art does not involve how to make ZSM-5 molecular sieve and β molecular sieve molecular sieve further have better catalytic cracking effect

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