采用改进的Othnmer汽相单循环平衡釜,在常压下测定了正己烷-甲基环戊烷-Ⅳ-甲基吡咯烷酮(NMP)三组分物系的汽液平衡数据.采用NRTL方程对实验数据进行关联,回归得到了NRTL方程的模型参数,汽相摩尔分数的实验值和计算值平均绝对相对偏差为1.96％.萃取精馏正己烷-甲基环戊烷适宜的萃取剂与原料的质量比(溶剂比)为8.模拟结果表明,采用NMP 为萃取剂,萃取精馏正己烷-甲基环戊烷适宜的条件为:溶剂比8、理论板数45、原料进料位置第26块塔板、萃取剂进料位置第7块塔板、回流比为2.在此条件下,塔顶馏分中正己烷的质量分数可达99.10％.%Vapor-liquid equilibrium data for hexane-methyl cyclopentane-N-methyl pyrrolidone ternary system were determined in an Othmer equilibrium still at atmospheric pressure (101. 3k Pa). The data were correlated by using NRTL equation and the model parameters were obtained by the nonlinear least squared criterion method. The results showed that the average relative deviation between the experimental data and the NRTL model data was 1. 96%. The extractive distillation process for separation of hexane-methyl cyclopentane with N-methyl pyrrolidone as the solvent was simulated. Under the optimized conditions of theoretical plate number 45, reflux ratio 2, mass ratio of solvent to feed 8, solvent feed 7th theoretical plate and feedstock 26th theoretical plate, the mass fraction of hexane in the top products could reach 99.10%.
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