乙酸光氯化反应制备氯乙酸工艺的研究

设计了一种新型实验室氯化反应器－－光照内环流气液反应器，应用于乙酸光氯化制氯乙酸的反应。该反应器具有光照效果好、易环流、密封性能好等。大环流反应器中考察了光照下不同反应温度对乙酸氯反应的影响，实测了不同温度下，乙酸、氯乙酸和二氯乙酸的浓度随反应时间的变化关系。将乙酸在环流反应器中的光氯伦反应结果与乙酐为催化剂的氯化反应结果进行了比较，发现光氯反应速率与乙酐为催化剂时的氯化速度时相当，但二氯乙酸生成量明显偏高，为了抑制二氯乙酸的生成，在光照的同时加入乙酐作为抑制剂，考察了不同的乙酐用量和加入方式对二氯乙酸生成的影响。

Study on the Preparation of Monochloroacetic Acid from the Photo-chlorination of Acetic Acid

This paper devised a new photo chlorination reactor in laboratory scale -- a gas liquid loop reactor, in which a light is placed. The reactor has advantages of good illumination and perfect sealing property. The effects of different temperature on the chlorination of HAc were researched. The relations between the concentration of HAc, MCA and DCA and time were measured. The results between photo chlorination and catalytic chlorination of acetic acid in the presence of acetic anhydride as catalyst in the loop reactor were compared. It was found that the rate of photo chlorination is nearly equal to that of catalytic chlorination of acetic acid. But the concentration of DCA in the presence of light is higher than that of in the presence of acetic anhydride. In order to inhibit the formation of DCA, acetic anhydride as inhibitor was added during the photo chlorination of acetic acid. It was studied that the influence of different concentration and different addition mode of the inhibitor on the formation of DCA.