精制L-乳酸的分子蒸馏工艺研究  

The Study of Refining L-Lactic Acid by Molecular Distillation

作　　者：许松林[1] 郑弢[1] 徐世民[1] 

机构地区：[1]天津大学精馏技术国家工程研究中心,天津300072

出　　处：《高校化学工程学报》2004年第2期246-249,共4页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金项目(20176037)。

摘　　要：分子蒸馏技术是一种在高真空条件下进行的连续蒸馏过程,适合于分离高沸点、热敏性及具有生物活性的混合物.今研究了用分子蒸馏技术对L-乳酸进行精制的工艺条件;实验过程中粗乳酸原料不需要进行其它脱水及脱色方法处理,只需通过两次分子蒸馏,即可得到高纯度的L-乳酸.考察了分子蒸馏工艺操作过程的蒸馏温度、进料速率、刮膜器转速等因素对L-乳酸收率及纯度的影响.发现适宜的分离工艺是:操作压力0.1Pa,蒸发温度55～75℃,进料速率90mL.h-1,刮膜器转速110～130rmin-1,其中蒸发温度和进料速率是影响产品L-乳酸纯度的最重要的因素.Molecular Distillation(MD) is a kind of high vacuum distillation method, which is suitable for the separation of high boiling, heat sensitivity and viscidity products. Refining L-lactic acid by MD was studied. High content purified L-lactic acid was produced by two steps of molecular distillation from the raw lactie acid without using any other methods for decoloritation and dehydration. During the process, the first step just focus on getting rid of the contained water, and the second step mainly on purifying the L-lactic acid. The optimal operation for the purification of L-lactic by MD was found as pressure 0.1Pa, evaporation temperature 55~75℃, feed rate 90mLh-1 and agitation speed 110~130rmin-1. Among all the operation parameters, evaporation temperature and feed flow rate are two key factors, which effect the purity of L-lactic acid primarily.

关 键 词：分子蒸馏 L-乳酸 精制 分离工艺 

分 类 号：TQ028.31[化学工程]