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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 n-heptane 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.