萃取精馏分离三甲氧基硅烷和甲醇的模拟和优化

Simulation and optimization of extractive distillation for separating methanol and trimethoxysilane

运用Aspen Plus对萃取精馏分离三甲氧基硅烷和甲醇进行了模拟研究。采用芳烃作溶剂,通过和传统的对二甲苯溶剂对比,发现异丙苯和均三甲苯作溶剂具有很好的节能效果,且均三甲苯效果十分显著。在均三甲苯作溶剂的基础上,分析了溶剂比、塔板数、进料位置、回流比等条件对分离效果的影响,并对参数进行优化。确定了最优的操作条件为萃取精馏塔共24块理论板,混合物进料位置为第15块塔板,溶剂进料位置为第11块板,溶剂比为0.4,回流比为0.6。溶剂回收塔共12块理论板,进料位置为第5块塔板,回流比为2.3。在此条件下,三甲氧基硅烷和甲醇的产品的质量分数均能达到99.6%。

Extractive distillation for separating methanol and trimethoxysilane is studied by Aspen Plus. Aromatic hydrocarbons are selected as the solvent. Compared with p-xylene solvent, isopropyl benzene and mesitylene are found to be energy-saving when they are used as solvents, especially for mesitylene. Using mesitylene as solvent, the effects of mass ratio of solvent to the mixture, stage numbers, feeding locations of the solvent and the mixture and reflux ratio on the separation effect are studied. The optimal conditions for extractive distillation are shown as follows ：24 theoretical plates, 15th stage and 11 th stage for the feeding locations of the mixtures and the solvent, respectively, 0.4 of solvent ratio and 0. 6 of reflux ratio of the extractive distillation column. Solvent recovery column has 12 theoretical plates and the stream is fed on the 5th stage. Reflux ratio of recovery column is 2. 3. Under these conditions, the mass fraction of methanol and trimethoxysilane products can reach 99.6%.