Glufosinate separation and purification method

Abstract

The invention belongs to the field of pesticide production and particularly relates to a glufosinate separation and purification method. According to the method, the separation and purification is started when a glufosinate hydrochloride reaction solution in the steps of distilling the glufosinate hydrochloride reaction solution under reduced pressure to remove dilute hydrochloric acid, adding ammonia water to adjust the pH to maximally produce ammonium chloride, distilling under reduced pressure to remove water, adding a flotation solvent for dispersion, placing the material into a chute at specific temperature and speed, performing flotation separation according to the difference in the proportion of a principal component and subsidiary salt, removing the solvent, dissolving the material in aqueous methanol to remove trace ammonium chloride, filling ammonia gas to adjust the pH value to 8, performing centrifugation and drying to obtain a final product. The glufosinate separation and purification method uses a flotation method for separating the principal component glufosinate and an intermediate of the principal component from the subsidiary salt ammonium chloride and the aqueous methanol for purification and is high in yield, good in purity, simple in process, low in cost and is suitable for industrial production.

Description

technical field [0001] The invention relates to the field of pesticide production, in particular to a separation and purification method for glufosinate-ammonium. Background technique [0002] Glufosinate-ammonium (glufosinate-ammonium or glufosinate) is a highly efficient, low toxicity, non-selective (killing) contact organophosphorus herbicide with partial systemic action. It has low toxicity, relatively safe, easy to degrade in soil, safe for crops, small drift, wide herbicidal spectrum, high activity, less dosage, less environmental pressure, and rapid weed killing, so it has broad market prospects. [0003] At present, there are many technical routes related to glufosinate-ammonium at home and abroad, among which the Stryker-Zelinsky method is more suitable for industrial production, but when it synthesizes glufosinate-ammonium, it will generate NH 4 Cl or NaCl and other by-products, and the separation and purification of glufosinate-ammonium by the usual crystallizati...

AI Technical Summary

Problems solved by technology

[0003] At present, there are many technical routes related to glufosinate-ammonium at home and abroad, among which the Stryker-Zelinsky method is more suitable for industrial production, but when it synthesizes glufosinate-ammonium, it will generate NH 4 Cl or NaCl and other by-products, and the separation and purification of glufosinate-ammonium by the usual crystallization method requires multiple recrystallizations to achieve the required purity requirements, and the more times of recrystallization, the lower the yield. The chemical reaction method represented by No. 201110160129.5 achieves the purpose of purifying glufosinate through the chemical reaction of esterification and hydrolysis. It needs two or three steps to complete the separation, which wastes raw materials, prolongs the number and time of processes, and due to the chemical reaction reduced yield