VC生产中集成工艺对酯化反应和膜分离性能的影响  

Influences of Integration Process on Membrane Separation Performance and Esterification Reaction in Vitamin C Production

作　　者：蔡邦肖 邸天梅 

机构地区：[1]浙江工商大学食品与生物工程学院膜科学与工程研究所,杭州310035 [2]浙江司大膜工程有限公司,杭州310012

出　　处：《中国食品学报》2009年第5期93-99,共7页Journal of Chinese Institute Of Food Science and Technology

基　　金：浙江省自然科学基金重点重大项目(ZC0204);浙江省"重中之重"项目

摘　　要：将膜技术应用于食品化学工业具有重大的创新意义。集成优先透水膜可以突破常规酯化反应平衡的限制,节约资源,提高产率。维生素C(VC)生产的关键工艺是甲醇与2-酮基-L-古龙酸(2-KLG)的甲酯化反应。基于PERVAPR2201膜与2-KLG甲酯化反应的集成工艺,分别进行甲醇/水二元体系、甲醇/2-KLG/2-Me-KLG/水四元体系的研究。试验结果表明,该集成工艺由于分离膜及时去除了酯化反应生成的副产物——水,迅速地改变了常规酯化反应状况。酯转率(η)随酯化反应液中水(CR-H2O)的减少而显著增加。η和膜的渗透汽化(PV)分离性能都明显受集成工艺的反应温度、初始料液醇酸比(R0)、分离膜面积和料液流量的影响。在膜与常规工艺集成的2-KLG甲酯化反应过程,η达99.06%,CR-H2O小于2mol/L,PV过程膜的渗透通量125～225g/(m2·h),渗透液中水含量(CP-H2O)大于80%。Application membrane technology to food chemical industry possesses imporlantly innovative significance. The integration process （IP） with permselective membrane of water may broke through the equilibrium-limited of conventional esterificafion reaction （CER）, save resource and increase yield of the product. One of key processes in production of Vitamin C is the methyl esterification reaction of 2-keto-L-gulonic acid （2-KLG）. The new IP systems of dual methanol/water, quaternary methanol/2-KLG/2-Me-KLG/water were studied respectively based on IP with PERVAP 2201 membrane in methyl esterification of 2-KLG. The experimental results showed that IP improved rapidly the reaction state occurred in CER, because the membrane integrated in IP can remove the byproduct water from esterification reaction in good time. The conversion rate （η） of 2-Me-KLG increased with decrease of the water content （CR=H2O） in esterification reaction mixture. The η and separation performance of membrane in pervaporation （PV） effected markedly by the reaction temperature, the mass ratio （R0） of methanol and 2-KLG in the initial reaction mixture, the membrane surface area and the feed flow rate. The η was 99.06%, CR-H2O was less than 2 mol/L, the PV fluxes were 125-225g/（m2.h）, the water content in the permeate （Cp-H2O） was more than 80 % for the IP with the membrane during this integration process.

关 键 词：维生素C 膜分离 酯化反应 食品化学 集成工艺 

分 类 号：TQ466.3[化学工程—制药化工]