Method for preparing ethylene sulfite by using microchannel reactor

Abstract

The invention discloses a method for preparing ethylene sulfite by a micro-channel reactor, which comprises the following steps of: performing nucleophilic substitution reaction in the micro-channel reactor at 30-50 DEG C by taking ethylene glycol and thionyl chloride as initial raw materials and chloralkane as a reaction solvent, and controlling the retention time of the reaction by controlling the flow rate of reaction liquid, and after the reaction is finished, collecting effluent of the microchannel reactor to obtain a crude product of the ethylene sulfite, separating the crude product of the ethylene sulfite, and carrying out desolvation and rectification to obtain an ethylene sulfite product. According to the method, the reaction efficiency and the product yield are greatly improved, the product selectivity reaches up to 97.89%, the product yield is increased to 96% from 91%, in addition, continuous production is achieved through the micro-channel reaction, the automation degree and safety are greatly improved, and compared with an existing process, the method has the advantages of being simple in technological process, short in production period, stable in product quality and the like.

Description

technical field [0001] The invention relates to the field of fine chemicals, in particular to a method for preparing vinyl sulfite in a microchannel reactor. Background technique [0002] Vinyl sulfite is an important intermediate in the preparation of vinyl sulfate, a film-forming additive for lithium-ion battery electrolytes, and its research methods have received extensive attention in recent years. At present, there are two main methods for synthesizing vinyl sulfite: ethylene oxide and sulfur dioxide or ethylene glycol and thionyl chloride are used as starting materials to prepare. The main problem of the method using ethylene oxide and sulfur dioxide as raw materials is that both ethylene oxide and sulfur dioxide in this method are toxic carcinogens, and ethylene oxide is flammable and explosive, not easy to transport long distances, and has very high storage requirements. high. In addition, the reaction also requires the use of a special catalyst, and the reaction n...

AI Technical Summary

Problems solved by technology

Using ethylene oxide and sulfur dioxide as raw materials, the main problem is that both ethylene oxide and sulfur dioxide are toxic carcinogens, and ethylene oxide is flammable and explosive, not easy for long-distance transportation, and requires very high storage requirements. high

[0003] In the traditional tank-type batch production process, due to the long reaction time or the local reaction temperature is too high, ethylene glycol produces more by-products of chloroethanol, which affects the selectivity of the product and makes subsequent separation difficult

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