A kind of preparation method of highly selective benzene alkylation strip catalyst

Abstract

Disclosed is a preparation method of a high-selectivity benzene alkylation strip-shaped catalyst. The preparation method comprises the steps that an MFI zeolite molecular sieve with a high silica-alumina ratio is selected as a catalyst precursor; hydrolysate of acidified silicone grease and the MFI zeolite molecular sieve with the high silica-alumina ratio are subjected to strip-extrusion formation, then separation mother liquor obtained when the MFI zeolite molecular sieve with the high silica-alumina ratio is subjected to hydrothermal crystallization is used for treating a formed catalyst, and boride is added into the separation mother liquor; an ion exchange method is adopted for converting the strip-extrusion formed object, treated with the mother liquor, of the MFI zeolite molecular sieve with the high silica-alumina ratio into the hydrogenated alkylation catalyst. According to the method, the mother liquor generated during the hydrothermal synthesis of the MFI zeolite molecular sieve with the high silica-alumina ratio is used for treating the formed strip-shaped catalyst, the useful components in the mother liquor are recovered, the pore passages of the catalyst are cleared,and the environmental pollution in the full production chain of the alkylation catalyst is reduced. When the formed catalyst is treated with the mother liquor, by adding an appropriate amount of boride into the mother liquor, the mechanical strength of catalyst particles is improved, and the service life of the catalyst is conveniently prolonged.

Description

technical field [0001] The invention belongs to the technical field of petrochemical catalysts, and relates to a preparation method of a benzene alkylation catalyst. Background technique [0002] The gas-phase alkylation of benzene, methanol and ethanol can be used to synthesize xylene and ethylbenzene, respectively. The former can be used to produce p-xylene and then terephthalic acid; the latter can be used to dehydrogenate styrene to produce polyphenylene. Ethylene etc. Because of the generation of water, the alkylation of benzene and methanol, benzene and ethanol can only be carried out under the reaction conditions of high temperature and gas phase, so it faces the following common problem: how to reduce the mutual isomerization side between xylene and ethylbenzene reaction. That is, in the alkylation of benzene and methanol, the further isomerization reaction of the target product xylene to the by-product ethylbenzene should be minimized. The ethylbenzene by-product...

AI Technical Summary

Problems solved by technology

Because the small amount of xylene impurities generated by this side reaction will affect the purity of downstream products of styrene, limiting its application range

[0003] The preparation method of the benzene alkylation catalyst disclosed by the existing patent does not solve the above problems well