甘油萃取精馏分离乙腈-正丙醇混合物模拟和优化

Simulation and Optimization of Separating Acetonitrile and N-propanol Mixture by Extractive Distillation Using Glycerol as Extractant

用甘油为萃取剂,在NRTL热力学模型下,利用AspenPlus软件来模拟乙腈-正丙醇混合物的萃取精馏分离,确定了萃取精馏塔和溶剂回收塔最优的馏出比,理论板数,进料位置,回流比以及溶剂比等工艺条件。模拟计算结果表明,甘油可以较好的实现乙腈和正丙醇的高纯度分离。在最优操作条件下,萃取精馏塔顶乙腈的含量高达99.55%,溶剂回收塔顶正丙醇的含量高达100%,整个萃取精馏过程中,乙腈的回收率高达100%,正丙醇的回收率高达98.87%,满足分离要求。

Using glycerol as the extractant, NRTL as the thermodynamic model, Aspen Plus simulated the extractive distillation of acetonitrile and n-propanol mixture. The process conditions such as distillate to feed ratio, theoretical plate number, feed stage, reflux ratio and solvent to feed ratio were determined. The simulation results showed that glycerol can achieve high purity separation of acetonitrile and n-propanol mixture. Under the optimum operating conditions, the content of acetonitrile at the top of the extractive distillation column was as high as 99.55%, and the content of n-propanol at the top of the recovery distillation column was as high as 100%. During the whole extractive distillation process, the recovery of acetonitrile was as high as 100%, and the recovery of n-propanol was as high as 98.87%, which satisfied the separation requirements.