摘要
本文对氰基乙酯实际生产中存在的换热不均、滴加时间长,乙亚胺酸乙酯盐酸盐易发生水解等工艺缺陷,进行了进一步的研究,通过增加溶剂氯仿的用量、提升换热效率,并对成盐时间、氰化时间、氰化pH、不同氰化pH调节剂进行了优化研究,对后期生产工作提供了经验和指导。结果表明,最佳工艺条件为:成盐步:氯仿用量200 g/mol乙腈,乙腈:乙醇:HCl摩尔比为1︰1.25︰1.39,成盐温度为0~5℃,反应时间16 h;氰化步:乙亚胺酸乙酯盐酸盐:单氰胺:氨水摩尔比为1︰1.15︰0.53,氰化温度为10~15℃,反应时间6 h,氰化时以氢氧化钠作为pH调节剂,调节pH=5.5~6.5,两步反应总收率可达84%以上,工业化时工艺可实施难度上也大为降低。
In this paper,the process defects such as uneven heat transfer,long dropping time and hydrolysis of ethyl iminate hydrochloride in the actual production of cyanoethyl ester were further studied.By increasing the amount of solvent chloroform,improving the heat exchange efficiency,and optimizing the salt forming time,cyanidation time,cyanidation pH and different cyanidation pH regulators,the experience and guidance for the later production work were provided.The results showed that the optimum process conditions were as follows:chloroform 200 g/mol acetonitrile.The molar ratio of acetonitrile:ethanol:HCl was 1︰1.25︰1.39.The salt forming temperature is 0~5℃ and the reaction time is 16 h.Ethyleneimine ethyl ester hydrochloride:cyanamide:ammonia molar ratio of 1︰1.15︰0.53.The cyaniding temperature is 10~15℃,the reaction time is 6 h.When cyanide is used as sodium hydroxide as pH regulator,the pH=5.5~6.5 is adjusted,and the total yield of the two step reaction can reach more than 84%.In industrialization,the process can be implemented with less difficulty.
作者
盛俊
马勇
沈杰
Sheng Jun;Ma Yong;Shen Jie(Jiangsu Ruiheng New Material Technology Co.,Ltd.,Lianyungang 222000,China)
出处
《广东化工》
CAS
2021年第21期66-67,69,共3页
Guangdong Chemical Industry
