Production process of diethyl phosphite

The invention provides a production process of diethyl phosphite. According to the production process disclosed by the invention, chloroethane is used as a diluent in the process of generating triethyl phosphite, so that too fast reaction of phosphorus trichloride and ethanol is avoided, further reaction of diethyl phosphite and hydrogen chloride is inhibited, and generation of by-products is reduced; through reactive distillation, unreacted triethyl phosphite continues to be converted into diethyl phosphite, and side reactions are avoided at the same time. The production process provided by the invention can be continuously carried out, can conveniently recover byproducts hydrochloric acid and chloroethane while obtaining high-purity diethyl phosphite with high yield, has very high practical value, and is suitable for industrial application. 本发明提供一种亚磷酸二乙酯生产工艺。本发明的生产工艺在生成亚磷酸三乙酯的过程中使用氯乙烷作为稀释剂，避免了三氯化磷与乙醇过快反应，抑制了亚磷酸二乙酯继续与氯化氢的进一步反应，减少副产物生成；通过反应精馏，未反应的亚磷酸三乙酯继续向亚磷酸二乙酯转变，同时避免了副反应发生。本发明的生产工艺可以连续进行，在高收率地得到高纯度的亚磷酸二乙酯的同