摘要
近些年,丙烯酸乙酯相关产业多采用气相固定床法,该方法存在能耗较高、设备投资大、生产切换不方便、丙烯酸单程转化率低和生产成本高等一系列问题.因此,本文研究了一种液相连续法生产丙烯酸乙酯的合成工艺路线以解决上述问题.以丙烯酸和95％乙醇为原料,采用液相连续法合成丙烯酸乙酯,其结构经1H NMR,13C NMR和HR-MS(EI)确证.研究了反应温度、停留时间、95％(质量分数)乙醇用量、催化剂用量(质量分数)和萃取剂用量对于液相连续法生产丙烯酸乙酯的影响.结果表明:在丙烯酸与95％乙醇物质的量之比为1.0∶2.0,第一级反应釜反应温度为75 ℃、第二级反应釜反应温度为80℃、第三级反应釜反应温度为90 ℃、反应停留时间为4 h、催化剂物质的量分数为0.4％(催化剂相对于丙烯酸原料的物质的量分数)和萃取液和萃取剂质量比为1.0:2.0的条件下丙烯酸乙酯单程收率达到95.0％,经工业级放大后丙烯酸乙酯单程收率达到95.3％.上述研究在一定程度上解决了气相固定床方法的一系列缺陷,为丙烯酸乙酯的工业生产提供了一种较为优异的生产方式.
Abstract
In recent years,ethyl acrylate related industries mostly use gas phase fixed bed,the method of high energy consumption,large equipment investment,production switching is not convenient,a-crylic acid one-way conversion rate is low,high production cost a series of problems,therefore,this experiment studied a liquid phase continuous production of ethyl acrylate synthesis process to solve the above problems.Ethyl acrylate was synthesized from acrylic acid and 95％ethanol by liquid phase continuous method.Its structure was characterized by 1H NMR,13 C NMR and MSI(EI).The effects of reaction temperature,residence time,95％ethanol dosage,catalyst mass fraction and extractant dosage on liquid phase continuous production of ethyl acrylate were studied.The results showed that:Under the conditions that acrylic acid is 1 equivalent,95％ethanol is 2 equivalent,the reaction tem-perature of the first stage reactor is 75 ℃,the reaction temperature of the second stage reactor is 80 ℃,the reaction temperature of the third stage reactor is 90 ℃,the reaction residence time is 4 h,the amount of catalyst is 1％of the mass of acrylic acid,and the extraction liquid mass is 1.0∶2.0,the yield of ethyl acrylate reaches 95.0％.The yield of ethyl acrylate was 95.3％after industrial amplifi-cation.The above research solves a series of defects of the gas phase fixed bed method to a certain ex-tent,and provides an excellent production method for the industrial production of ethyl acrylate.
维普
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