乙酸乙酯和水萃取精馏分离溶剂的研究

Selection of Composite Extractive Distillation Solvent for Ethyl Acetate-Ethanol-Water

从简化生产工艺、降低分离过程能耗及一次性将乙酸乙酯浓度提高到99.5%以上出发,提出采用复合萃取法分离乙酸乙酯和水,从乙酸乙酯、水与溶剂分子之间存在的诱导力、静电力、色散力及氢键出发,对12类溶剂进行分析和对比,提出可选用多元醇、水、羧酸、胺类、酮作为萃取溶剂;采用单级汽液平衡釜研究各种溶剂对乙酸乙酯和水相对挥发度的影响,经测定以甘油为溶剂,乙酸乙酯与水的相对挥发度达8.9以上;研究在不同温度、溶液比的条件下,相对挥发度的变化情况,为进一步实验研究提供依据.

The composite extractive separation (different extractive agents at different positions) of ethyl acetate and water is proposed for the aims of simplifying production technology, reducing energy consumption agents and once raising the concentration of ethyl acetate to over 99.5%. All kinds of agents composed of single, binary, ternary components are summarized. Upon the shortages of systematic researches and comparisons of extractive agents, in the paper extractive agents are classified into twelve types from the interactions between molecules, electrostatic force, dispersion force, hydrogen bond, et al. The effects of all kinds of extractive agents on separation of ethyl acetate and water system are analyzed, and polybasic alcohol, water, carboxylic acid, amides and ketone are chosen as separation agents for ethyl acetate and water system. Affection of temperature and solvent ratio on relative volatility is studied, with measured data from the checked pot, combined with other influencing factors, glycerol is selected as extractive solvent for ethyl acetate/water system.