萃取精馏法分离甲醇/乙酸乙酯/乙酸甲酯共沸物的研究  

Research on separating azeotropes of methanol/ethyl acetate/methyl acetate with extractive distillation method

作　　者：曹君[1] 贺来宾[1] 杨卫胜[1] 

机构地区：[1]中国石化上海石油化工研究院,上海201208

出　　处：《计算机与应用化学》2014年第7期812-816,共5页Computers and Applied Chemistry

摘　　要：由于甲醇／乙酸乙酯和甲醇／乙酸甲酯体系均存在共沸现象，因此对于甲醇，乙酸乙酯／乙酸甲酯三元混合物，采用普通的精馏方法很难将甲醇有效分离。本文采用萃取精馏的方法，首先分别比较了不同萃取剂对甲醇／乙酸乙酯和甲醇／乙酸甲酯体系相对挥发度的影响，并选择较为合适的萃取剂。接着利用流程模拟软件AspenPlus对萃取精馏过程进行了全流程模拟，并对溶剂比、萃取塔理论塔板数、原料与萃取剂进料位置、萃取剂进料温度等因素对分离效果的影响进行了考察，得出了如下较优的工艺参数：萃取塔理论板数为80块，萃取塔原料进料位置为第19块板，萃取塔萃取剂进料位置为第3块板，萃取塔萃取剂进料温度为40℃，溶剂比为3．0；回收塔理论板数为5块，进料位置为第3块板。通过萃取精馏分离工艺，得到的甲醇产品纯度达到0．999以上，其中的羰基化合物质量含量小于20×10^-6，符合国标GB338-2011中优等品的标准。For the methanol, ethyl acetate and methyl acetate formed azeotropes, it was hard for them to be separated by the simple distillation. The extractive distillation method was adopted in this paper, the influence of different extractive agents on the relative volatility of the methanol/ethyl acetate/methyl acetate system was firstly compared and the proper extractive agent was chosen. The Aspen Plus software was then used to simulate the extractive distillation process, and the influences of the solvent ratio, theoretical plated number, feed tray and feed temperature for the extractive agent on the separation effect were investigated, the optimal parameters were obtained as follows： the theoretical plate number for the extractive distillation column and the recovery column of 80 and 5 respectively, the feed tray for the feed and the extractive agent for the extractive distillation column of the 19th and the 3rd tray respectively, the feed tray for the recovery column of the 3rd tray, the feed temperature for the extractive agent of 40 ℃and the solvent ratio of 3.0. Through the extractive distillation separation process, the methanol product purity reached more than 0.999, in which the mass purity of the carbonyl compound was less than 20 × 10^-6, which met the national standard GB338-2011.

关 键 词：甲醇 乙酸乙酯 乙酸甲酯 萃取精馏 二甲基亚砜 

分 类 号：TQ015.9[化学工程] TP391.9[自动化与计算机技术—计算机应用技术]