Preparation method for MFI/MOR composite zeolite molecular sieve catalyst without binder

Abstract

The invention relates to a preparation method for an MFI / MOR composite zeolite molecular sieve catalyst without a binder, which mainly solves the problem that an MFI / MOR composite zeolite molecular sieve prepared by the prior art has low activity if a binder is contained and has poor strength if no binder is contained. In the invention, an MFI / MOR composite zeolite molecular sieve without any binder is obtained through the following scheme: 20 to 80% of an MOR zeolite molecular sieve, 5 to 20% of aluminum compound and 10 to 80% of silicon oxide are mixed, molded and dried so as to obtain a preformed catalyst precursor mixture I, wherein the weight of aluminum compound is less than that of the silicon oxide; the mixture I is put in template steam and crystallized at a temperature of between 130 to 200 DEG C for 20 to 200 hours so as to obtain an MFI / MOR composite zeolite molecular sieve precursor without any binder; the catalyst precursor is dried and baked at a temperature of between 400 to 600 DEG C for 2 to 10 hours. The MFI / MOR composite zeolite molecular sieve obtained through the scheme can solve the above-mentioned problem and can be used as a catalyst to convert C4 hydrocarbon to alkene and aromatic hydrocarbons.

Description

technical field [0001] The invention relates to a preparation method of a binder-free MFI / MOR composite zeolite molecular sieve catalyst. Background technique [0002] Zeolite molecular sieves are widely used in the field of catalysis because of their uniform and ordered micropores, large specific surface area, and high hydrothermal stability. Due to the small particle size, zeolite powder is very inconvenient in practical application, and has weaknesses such as difficult recovery, easy deactivation and aggregation, so it needs to be shaped in advance. Generally, a binder needs to be added during the molding process, but after adding the binder, on the one hand, the binder has a certain pore blocking effect on the molecular sieve, which affects the diffusion performance; on the other hand, the addition of the binder also substantially affects the molecular sieve. The active center has a "dilution" effect, making the actual reaction space velocity larger, leading to faster d...

AI Technical Summary

Problems solved by technology

[0008] The technical problem to be solved by the present invention is that the MFI / MOR composite zeolite molecular sieve catalyst prepared by the prior art has low activity when containing a binder, poor strength when not containing a binder, and MFI or MOR single zeolite molecular sieves in catalysis, adsorption The problem of diffusion and adsorption limitation of compounds outside the pore size range of molecular sieves in other fields, providing a new method for the preparation of binder-free MFI / MOR composite zeolite molecular sieves

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