论文部分内容阅读
本实验采用了氯乙酸碱性水解法合成羟基乙酸的工艺路线,以氯乙酸和氢氧化钠为主要原料,碘化钠为催化剂进行反应。本实验采用单因素法对单个影响因素(反应温度、反应时间、催化剂的量)进行研究,得到的最优化条件是:反应温度为90℃,反应时间为8小时,催化剂用量与氯乙酸的质量比为0.8%。该反应为亲核取代反应。反应时,反应物氢氧化钠与氯乙酸钠的物质的量的比为1.1:1。用酸碱滴定法来计算羟基乙酸的产率,首先用乙醚对产物进行萃取,除去未水解的氯乙酸,然后用标定好的氢氧化钠溶液进行滴定,计算得羟基乙酸的产率可达到73.1%。
In this experiment, the process of synthesis of glycolic acid by basic hydrolysis of chloroacetic acid was adopted. With chloroacetic acid and sodium hydroxide as the main raw materials, sodium iodide was used as the catalyst. In this experiment, single factor method was used to study the single influencing factors (reaction temperature, reaction time, the amount of catalyst). The optimum conditions were: the reaction temperature was 90 ℃, the reaction time was 8 hours, the amount of catalyst and the mass of chloroacetic acid The ratio is 0.8%. The reaction is a nucleophilic substitution reaction. During the reaction, the ratio of the amount of substance sodium hydroxide to sodium chloroacetate is 1.1: 1. Acid-base titration was used to calculate the yield of glycolic acid. The product was extracted with diethyl ether to remove unhydrolyzed chloroacetic acid and titrated with calibrated sodium hydroxide solution. The yield of glycolic acid was 73.1 %.