Continuous flow preparation process of hydroxyethyl ethylenediamine
Hydroxyethyl ethylenediamine was synthesized from ethoxylation of ethylenediamine and ethylene oxide in a continuous flow microreactor with special microstructure.The effects of molar ratio of materials,water content of ethylenediamine,reaction temperature and residence time on the reaction were then analyzed.The results showed that under the optimal conditions of n(ethylenediamine)∶n(ethylene oxide)= 3∶1,water content of ethylenediamine being 0.96%(mass fraction),reaction temperature of 80 ℃,and residence time of 60 s,the conversion of ethylene oxide was close to 100%,the selectivity of hydroxyethyl ethylenediamine was 87.4%and the selectivity of dihydroxyethyl ethylenediamine was 9.2%,while in the batch kettle reactor,the selectivity of hydroxyethyl ethylenediamine was 83.5%and the selectivity of dihydroxyethyl ethylenediamine was 15.9%with the same material ratio and reaction temperature.Therefore,the continuous flow microreactor could effectively improve the selectivity of hydroxyethyl ethylenediamine,reduce the occurrence of side reactions,greatly shorten the reaction time and boost the reaction efficiency.
ethylene oxideethoxylation reactionhydroxyethyl ethylenediaminecontinuous flow microreactorfine chemical intermediates