关键词: 乙苯, 烷基化, ZSM-5, 干气, 工业侧线

Abstract: A 1.0 kt/a industrial sidestream unit was built by simulating the alkylation reaction unit process of an industrial ethylbenzene plant in a refinery. Taking the new nano-ZSM-5 molecular sieve catalyst HC-501 as the research object, the performance of gas-phase alkylation of catalytic cracking dry gas and benzene was investigated. The catalyst loading method corresponds to the single-stage reaction bed layer of the industrial unit. The test results show that under the conditions of a reaction temperature of 330—370 °C, a molar ratio of benzene to ethylene (referred to as benzene-ethylene ratio) of 20—24, and an ethylene mass space velocity of 0.20—0.50 h^-1, the ethylene conversion rate is greater than 99.8%, the selectivity of ethylbenzene (including ethylbenzene and diethylbenzene, the same below) is greater than 99.0%, and the mass fraction of the main by-product xylene is less than 800 μg/g. Referring to the process conditions of the existing industrial unit, an energy consumption calculation model was established by using the simulation software Aspen Hysys to study the energy consumption under different temperatures and different benzene-ethylene ratios. The results show that for the existing industrial unit, when the benzene-ethylene ratio of the single-stage bed is reduced to 20—24 by using the catalyst developed in this study, the energy consumption of the alkylation + benzene circulation unit can be reduced by 12%—20%.

Key words: ethylbenzene, alkylation, ZSM-5, dry gas, industrial sidestream