Method for preparing high-content double-transition metal composite molecular sieve

Abstract

The invention relates to a method for preparing a high-content double-transition metal heteroatom composite molecular sieve. By using a stepwise synthesis method, a a MFI primary structure is firstly synthesized; then a M1-MFI molecular sieve is taken as part of silicon sources wherein M1 is one or two selected from the group consisting of Ni, Co, Cu, Fe, Zn, Cr and the like; M1-MFI is introduced into the hole wall of a mesoporous M2-MCM-41 molecular sieve wherein M2 is one or two selected from the group consisting of Ni, Co, Cu, Fe, Zn, Cr and the like; amorphous substances are guided to arrange in order to change defects of amorphous hole wall of the mesoporous molecular sieve, increase the wall thickness and raise heat stability and hydro-thermal stability of the mesoporous M2-MCM-41 molecular sieve. In the mean time, ion association complex formed by the interaction between a traditional template and a metal coordination compound is taken as a template of the synthesis molecular sieve, and metal ion is directly introduced into the molecular sieve skeleton through the template, successfully designing and synthesizing the double-transition metal heteroatom composite molecular sieve. The above composite molecular sieve material has well-regulated crystal structure, high metal content, two uniform mesoporous apertures, large specific surface area and pore volume, and good heat stability and hydro-thermal stability.

Description

1. Technical field [0001] The invention relates to a preparation method of a high-content double-transition metal composite molecular sieve, in particular to a high-content double-transition metal composite molecular sieve M 1 -MFI / M 2 -MCM-41(M 1 , M 2 = one or two of Ni, Co, Cu, Fe, Zn, Cr, etc.) Ni-MFI / Ni-MCM-41, Ni-MFI / Co-MCM-41, Co-MFI / Ni-MCM-41, Co-MFI / Co-MCM-41, Ni-MFI / Fe-MCM-41, Cu-MFI / Fe-MCM-41, Zn-MFI / Cr-MCM-41, Fe-MFI / Cr-MCM-41, etc. Preparation method of composite molecular sieve. 2. Background technology [0002] As we all know, ZSM-5 is an important microporous zeolite molecular sieve shape-selective catalyst in the modern petroleum industry. However, due to the limitation of its pore size, the product molecules are not easy to diffuse out in some reactions, which often leads to the occurrence of side reactions. With the heavy oil, solving the catalytic cracking of heavy oil and residual oil has become the controlling factor of the petroleum catalytic cra...

AI Technical Summary

Problems solved by technology

[0006] 1. Purpose of the invention: the present invention provides a high-content double-transition metal composite molecular sieve M 1 -MFI / M 2 -MCM-41(M 1 , M 2 =Ni, Co, Cu, Fe, Zn, Cr etc. one or both) synthetic method, its purpose is to overcome the defect that microporous molecular sieve is limited by pore size and poor thermal stability and hydrothermal stability of mesoporous molecular sieve, simultaneously Incorporation of a large number of metal atoms into the framework of molecular sieves

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