Method for preparing catalyst for alkylation reaction of methylbenzene and ethylene for synthesizing paramethyl ethylbenzene

Abstract

The invention relates to a method for preparing a catalyst for an alkylation reaction of methylbenzene and ethylene for synthesizing paramethyl ethylbenzene. The catalyst consists of the following components in part by weight: 50 to 90 parts of hydrogenous silicon-aluminum zeolite, 10 to 50 parts of binder, 5 to 8 parts of sesbania cannabina pers powder and 1 to 8 parts of at least one metal oxide of alkalinous metal oxides, wherein the hydrogenous silicon-aluminum zeolite is subjected to liquid-phase silicon deposition surface modification and the mole ratio of silicon dioxide (SiO2) to aluminium trioxide (Al2O3) is 40 to 300. The catalyst solves the problems of low methylbenzene conversion rate, serious side reactions such as a disproportionation reaction, an isomerization reaction and the like and high deactivation rate in the prior art well. In the reaction for synthesizing the paramethyl ethylbenzene, the reaction temperature is between 350 and 440 DEG C; the pressure is 0.1 to 1.5 MPa; the ratio of benzene to alkene is 1.0 to 6.0; and the space velocity is 1 to 10 h<-1>. The prepared catalyst is applied to a methylbenzene alkylation process for synthesizing the paramethyl ethylbenzene by using the methylbenzene and the ethylene and has high catalytic reaction selectivity.

Description

technical field [0001] The invention relates to a method for preparing a catalyst for the synthesis of p-methylethylbenzene by the alkylation of toluene and ethylene. The prepared catalyst can be used in the chemical production of p-methylethylbenzene, especially for the synthesis of p-methylethylbenzene with high selectivity. position methyl ethyl benzene product, and avoid the production of m- and ortho-position methyl ethyl benzene by-products. Background technique [0002] Dehydrogenation of p-methylethylbenzene can produce p-methylstyrene, which can be polymerized to produce a new type of plastic, polymethylstyrene. The polymer is superior to existing polystyrene plastics in terms of specific gravity, heat resistance, transparency and shrinkage. In addition, p-methylstyrene can be copolymerized with other monomers, which can improve the heat resistance and flame retardancy of some polymers, and can be widely used in the manufacture of engineering plastics, alkyd resin ...

AI Technical Summary

Problems solved by technology

[0005] The above documents have improved the para-selectivity and para-selectivity of p-methylethylbenzene, but the toluene conversion rate of total product selectivity is still low, which cannot meet the needs of actual production, thus limiting its industrial application.