萃取抽提C_(10)重芳烃中均四甲苯的萃取剂筛选

采用萃取精馏法分离C10重芳烃中的关键组分,根据萃取剂选择条件,初步确定选用环丁砜、邻苯二甲酸二甲酯、邻苯二甲酸二丁酯、邻苯二甲酸二辛酯、甘油和二苯胺为萃取剂;建立了汽液相平衡测定装置,测定了关键组分间的相对挥发度,确定邻苯二甲酸二辛酯为萃取剂;用AspenPlus软件进行模拟计算,在较佳模拟条件(T1塔板数为50块、原料进料位置为第18块塔板、回流比为5;T2塔板数为40块、侧线进料位置为第20块塔板、萃取剂进料位置为第10块塔板、萃取比(萃取剂与进料的体积比)为3.0、回流比为5;原料进料量为0.1L/h)下,可分别获得质量分数为60.3%和37.4%的均四甲苯和偏四甲苯,为均四甲苯结晶和偏四甲苯异构化提供原料。

Screening of Extractant for Extractive Distillation of Durene from C10 Heavy Aromatics

A extraction distillation process for separations of both durene and isodurene from C10 heavy aromatics was developed.Relative volatilities of main components in the C10 heavy aromatics in different extractants,namely sulfolane,dimethyl phthalate,dibutyl phthalate,dioctyl phthalate and glycerol,diphenylamine,were determined in a vapor-liquid equilibrium device to select appropriate extractant for the extraction distillation process.Results showed that dioctyl phthalate was the best.Simulation calculation of the extraction distillation of the C10 heavy aromatics was carried out,the optimal operation conditions were obtained and the process parameters of tower tray were designed by means of the Aspen Plus software.Under the optimal operation conditions:theoretical tray number of T1 50,feed tray 18th,reflux ratio 5;theoretical tray number of T2 40,feed tray 20th,extractive feed tray 10th,volume ratio of the extractant to feed 3.0,reflux ratio 5;and feed flowrate at inlet 0.1 L/h,60.3%(mass fraction)of durene as raw material of crystallization and 37.4%(mass fraction)of isodurene as raw material of isomerization could be obtained.