Device and process for applying dimethyl phosphite byproduct hydrogen chloride to synthesis of glyphosate

Abstract

The invention provides a method and a device for applying dimethyl phosphite hydrogen chloride tail gas to synthesis of glyphosate. The method comprises the following steps: conveying dimethyl phosphite tail gas into a compressor through a pipeline, and carrying out primary pressurized condensation to obtain a high-boiling-point alcohol water solution and non-condensable gas; carrying out cryogenic treatment on the non-condensable gas in a secondary pressurized condenser, separating the product to obtain hydrogen chloride gas, and storing the hydrogen chloride gas in a hydrogen chloride gas cabinet; carrying out an acidolysis reaction on the hydrogen chloride gas and the synthesis liquid in a hydrolysis kettle, then carrying out heating desolvation and deacidification and feeding the product into a cooling crystallization process; and then carrying out solid-liquid separation through a washing device, and finally drying the product to obtain the glyphosate raw medicine. According to the method, the hydrogen chloride and the methyl chloride are separated through pressurization and condensation, then the methyl chloride enters a refining procedure, and the separated hydrogen chlorideis applied to the glyphosate production mode, so that the introduction of water in a reaction system can be reduced, the steam consumption during solvent recovery is reduced, and the wastewater amount is reduced. The water for glyphosate production is reduced, the wastewater treatment and energy consumption are reduced at the same time, and the economic and environmental benefits are remarkable.

Description

technical field [0001] The invention belongs to the technical field of glyphosate production by dimethyl phosphite and alkyl ester method, and specifically relates to a method and a device for applying dimethyl phosphite hydrogen chloride tail gas to glyphosate synthesis. Background technique [0002] Glyphosate, also known as Roundup, is a non-selective systemic conduction herbicide. There are two mainstream production methods of glyphosate, one is the production method using iminodiacetic acid (IDA) as the raw material, and the other is the production method using glycine and alkyl phosphite as the raw material. In my country, the synthesis of glyphosate by the glycine-alkyl ester method occupies a dominant position. The specific process is as follows: triethylamine is used as a catalyst, and paraformaldehyde is depolymerized in the solvent methanol to form hemiacetal, which is further reacted with glycine and then combined with Dimethyl phosphite is esterified, and then t...

AI Technical Summary

Problems solved by technology

[0004] In this method, 1 ton of glyphosate produces about 3.6 tons of acidic mother liquor, and a large amount of high-salt mother liquor increases the cost of environmental protection treatment

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