Method for preparing glycol sulfite

Abstract

The preparation method for ethylene sulfite comprises: with dimethyl sulfite and glycol as material without ratio limit and 0.01-5wt% p-toluenesulfonic acid as catalyst, heating from 60-70Deg to 160-180Deg gradually while removing continually the generated methanol to promote the reaction tend to completeness; finally, fractionating and purifying to obtain the product. This invention has high yield and purification with no corrosion to device.

Description

technical field [0001] The invention relates to the field of chemical synthesis, in particular to a preparation method of ethylene sulfite. Background technique [0002] Ethylene sulfite is a raw material for organic synthesis and can be used as a solvent or additive for electrolytes of lithium secondary batteries. At present, the method of producing ethylene sulfite mainly contains the following several kinds: [0003] (1) prepare ethylene sulfite with the method for oxirane and sulfur dioxide reaction, this method security is relatively poor, very high to equipment and operation requirement; [0004] (2) Ethylene sulfite is prepared by reacting ethylene glycol with thionyl chloride. Although the method is low in cost, thionyl chloride is highly toxic, and the reaction generates a large amount of acid gas, which is difficult to purify after treatment. Usually The content of impurities such as chloroethanol is very high; [0005] (3) prepare ethylene sulfite with the meth...

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Problems solved by technology

[0003] (1) prepare ethylene sulfite with the method for oxirane and sulfur dioxide reaction, this method security is relatively poor, very high to equipment and operation requirement;

[0004] (2) prepare ethylene sulfite with the method for ethylene glycol and thionyl chloride reaction, although this method is low in cost, thionyl chloride toxicity is big, and reaction generates a large amount of acid gases, and post-treatment purification is more difficult, usually The content of impurities such as chloroethanol is very high;

[0005] (3) prepare ethylene sulfite with the method for polyethylene glycol sulfite depolymerization, this method is not too practical;

[0006] (4) Ethylene sulfite is prepared by reacting ethylene glycol with dimethyl sulfite. If this method does not have a catalyst, it can be carried out, but the reaction time needs to be very long, and the reaction is not carried out completely.

And this ethylene sulfite is not suitable for use as a solvent or additive for lithium secondary battery electrolyte, they will affect the storage stability of the electrolyte