摘要
针对传统硝酸氧化乙二醛制备乙醛酸存在周期长、选择性低等问题,本文提出了一种在微反应器中高选择性合成乙醛酸的方法。先将35%硝酸与40%乙二醛按照一定摩尔比输送到T形微混合器,在微通道和降膜微反应器中反应一段时间,将得到的乙醛酸反应液再和硝酸以一定摩尔比输送到T形微混合器、微通道以及降膜微反应器中,循环几次后得到最终反应液。结果表明:当硝酸(流速0.13 mL/min)与乙二醛(流速0.24 mL/min)初次混合的摩尔比为0.42∶1、硝酸(流速0.02 mL/min)与收集的乙醛酸反应液(流速0.24 mL/min)混合反应6次、T形微混合器与微通道的温度和停留时间分别为60℃和2 min、降膜微反应器反应温度为90℃时,乙二醛转化率为82%,乙醛酸选择性可达95%。
To solve the problems such as long production time and low selectivity in traditional methods for the preparation of glyoxylic acid from the oxidation of glyoxal,a modified synthesis by taking advantage of the microreactor was developed.35%nitric acid and40%glyoxal of a certain ratio were mixed in a T-micromixer,and the mixture was passed by the microchannel and the falling film microreactor for a certain residence time.The resultant solutions were mixed with nitric acid in a certain ratio again.After several cycles,the glyoxylic acid reaction solutions were obtained.Results showed that the conversion rate of glyoxal and the glyoxylic acid selectivity could reach82%and95%when the reaction was performed by a procedure with six cycles under the following conditions:initial mixture molar ratio of nitric acid(0.13mL/min)to glyoxal(0.24mL/min)of0.42∶1,the flow rate of glyoxylic acid reaction solutions of0.24mL/min,the flow rate of nitric acid of0.02mL/min,the residence time and reaction temperature in the T micromixer and microchannel of2min and60℃,and the reaction temperature in the falling film microreactor of90℃.
作者
王超
邓秋林
陈超
沈如伟
张利雄
WANG Chao;DENG Qiulin;CHEN Chao;SHEN Ruwei;ZHANG Lixiong(State Key Laboratory of Materials Oriented Chemical Engineering,College of Chemical Engineering,Nanjing Tech University,Nanjing 210009,China;School of Materials Science and Engineering,Southwest University of Science and Technology,Mianyang 621000,China)
出处
《南京工业大学学报（自然科学版）》
CAS
北大核心
2018年第1期66-73,共8页
Journal of Nanjing Tech University(Natural Science Edition)
基金
国家科技支撑计划(2015BAD15B00)
关键词
微反应器
降膜微反应器
乙二醛
乙醛酸
氧化
microreactor
falling film microreactor
glyoxal
glyoxylic acid
oxidation
