Method for dissociating ethanamidine in acetamidine hydrochloride by liquid caustic soda and methyl alcohol mixed solution

Abstract

The invention provides a method for dissociating ethanamidine in acetamidine hydrochloride by a liquid caustic soda and methyl alcohol mixed solution. The method comprises the following steps: I, preparing the liquid caustic soda and methyl alcohol mixed solution, and preparing an acetamidine hydrochloride and methyl alcohol mixed solution; II, adding the liquid caustic soda and methyl alcohol mixed solution and the acetamidine hydrochloride and methyl alcohol mixed solution into a rotary evaporator, and evaporating the mixed solutions through the rotary evaporator; III, conveying the evaporated methyl alcohol solution into a distilling tower for recycling methyl alcohol; IV, filtering the solution in the rotary evaporator, washing an obtained filter cake with a little of methyl alcohol, and drying the filter cake to obtain a sodium chloride solid; V, generating 10 to 20 percent of liquid caustic soda and 10 to 20 percent of hydrochloric acid from the sodium chloride solid through a film treatment technology, concentrating the liquid caustic soda till the content is 32 percent, and putting the liquid caustic soda serving as a raw material into operation. According to the method, byadoption of liquid caustic soda and methyl alcohol for dissociation, the utilization rate of the liquid caustic soda is increased; after byproducts of the liquid caustic soda are washed and dried, the sodium chloride is obtained, and 100% recycle can be realized through the film treatment technology, so that the production cost is greatly reduced, and the environmental problems caused by free salt which are the byproducts are eliminated.

Description

technical field [0001] The invention belongs to a method for dissociating acetamidine, and more specifically relates to a method for dissociating acetamidine from acetamidine hydrochloride with a mixture of lye and methanol. Background technique [0002] Acetamidine hydrochloride free acetamidine first process uses 20%-40% liquid sodium methoxide free. A large amount of free salt is produced during the freeing process, which cannot be recycled as a by-product, which increases the production cost and causes certain environmental pollution; a large amount of methanol is produced by-product, which cannot be comprehensively utilized and sold at a low price; liquid sodium methoxide itself has a strong Corrosiveness increases the risk of production safety, and its strong moisture absorption affects its properties and the quality of subsequent products. Contents of the invention [0003] The purpose of the present invention is to provide a method for the free acetamidine of acet...

AI Technical Summary

Problems solved by technology

A large amount of free salt is produced during the freeing process, which cannot be recycled as a by-product, which increases the production cost and causes certain environmental pollution; a large amount of methanol is produced by-product, which cannot be comprehensively utilized and sold at a low price; liquid sodium methoxide itself has a strong The corrosiveness increases the risk of production safety, and has a strong moisture absorption that affects its properties and the quality of subsequent products