间歇萃取精馏分离环己烷-正丙醇的研究

Separation of cyclohexane-1-propanol by batch extractive distillation

首次研究了间歇萃取精馏方法分离环己烷-正丙醇二元共沸物。通过溶剂选择原理选出DMF作为分离此共沸物系的溶剂,采用UNIFAC模型对常压下环己烷-正丙醇物系和加入溶剂DMF后的物系进行气液平衡模拟,并进行了实验验证,其中模拟结果与实验数据吻合较好。通过间歇萃取精馏分离此共沸物的实验研究来进一步考察所选萃取剂的效果。结果表明,DMF能够消除环己烷-正丙醇共沸物系的共沸点,采用有30块理论板的填料塔,萃取剂进料位置为第4块板,溶剂质量比为1∶1,回流比为3∶1时,塔顶环己烷产品质量分数为96.2%,回收率为72.2%。

The separation of cyclohexane-1-propanol azeotrope by batch extractive distillation is investigated in this study.DMF is chosen as solvent for separating cyclohexane-1-propanol azeotrope by extractive distillation according to the basic selection rules.The simulation of vapor-liquid equilibrium for cyclohexane-1-propanol with and without DMF under atmospheric pressure is performed using UNIFAC model.The vapor-liquid equilibrium experiment is also studied as well.The simulation results agree well with the experimental data.Then the batch extractive distillation experiment is done to investigate the effectiveness of the selected solvent.The results show that DMF can eliminate the azeotropic point of cyclohexane-1-propanol azeotrope.The batch distillation is carried out in a packed column of 30 theoretical plates and extractive solvent flowing inside on the fourth plate.The reflux ratio is 3 and the solvent ratio 1∶ 1.The concentration of cyclohexane obtained at the top of the column is 96.2wt%,and the recovery ratio is 72.2%.