萃取精馏法分离乙酸乙酯-正庚烷的研究  

Separation of ethyl acetate and n-heptane by Extractive Distillation

作　　者：康伟 李明雪 武艳艳 陈静[1] 高瑞昶[1] KANG Wei;LI Ming-xue;WU Yan-yan;CHENG Jing;GAO Rui-chang(School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, Chin)

机构地区：[1]天津大学化工学院,天津300072

出　　处：《现代化工》2017年第12期167-170,共4页Modern Chemical Industry

摘　　要：通过萃取精馏法,以N-甲基吡咯烷酮(NMP)为萃取剂分离乙酸乙酯-正庚烷的共沸物系。利用溶剂选择原理和UNIFAC基团贡献法筛选N-甲基吡咯烷酮作为萃取精馏的萃取剂,同时通过常压下乙酸乙酯-正庚烷体系和加入萃取剂N-甲基吡咯烷酮后的气液平衡实验,证明N-甲基吡咯烷酮能够打破共沸。并进行间歇萃取精馏实验,填料塔理论塔板数为35,回流比1.0,可以得到质量分数为98.3%的正庚烷,回收率为73.4%。最后在Aspen Plus软件帮助下研究N-甲基吡咯烷酮连续萃取精馏分离乙酸乙酯-正庚烷物系的工艺流程,萃取精馏塔塔顶正庚烷的质量分数可达99.5%,溶剂回收塔塔底回收纯N-甲基吡咯烷酮套用,为进一步的工业应用提供依据。N-methyl pyrrolidone was chosen as the solvent for separation of ethyl acetate and n-heptane system in extractive distillation by the UNIFAC group contribution method. The vapor-liquid equilibrium for ethyl acetate and nheptane system with N-methyl pyrrolidone under atmospheric pressure was performed. It indicated N-methyl pyrrolidone can effectively break the azeotrope system.With the reflux ratio of 1. 0,the mass fraction of n-heptane reaches 98. 3% in a packed column of 35 theoretical plates,and the recovery was about 73. 4%.Finally,Aspen Plus was used to simulate the separation of ethyl acetate and n-heptane system in continuous extractive distillation process.The n-heptane was obtained with mass fraction of 99. 5% at the top of the extractive distillation column and N-methyl pyrrolidone was recycled at the bottom of solvent recovery tower.The study can provide reference for further industrial application.

关 键 词：萃取精馏 乙酸乙酯 正庚烷 N-甲基吡咯烷酮 模拟 

分 类 号：TQ028[化学工程]