A kind of continuous production process for preparing glufosinate-ammonium

Abstract

The invention discloses a continuous production process for preparing glufosinate, which includes the following steps: 1) mixing a phosphonitrilic liquid and hydrochloric acid and feeding the mixture into a hydrolysis column, hydrolyzing the mixture to obtain a low-boiling-point substance, and condensing the low-boiling-point substance through a condenser to recycle ethanol; 2) feeding a kettle liquid generated in the hydrolysis into a hydrochloric acid flash evaporator to separate hydrochloric acid, feeding the hydrochloric acid into a hydrochloric acid absorber and a concentrate into a crystallization kettle, and feeding a crystallized material in the crystallization kettle into a centrifuge to prepare a glufosinate crude product; 3) feeding a centrifugal mother liquid back to the hydrochloric acid flash evaporator. The continuous acidolysis method solves the defects in an acidolysis reaction in a Strecker method in our country due to intermittent production, is short in production time and high in production efficiency, is low in environment-protection load, and is low in production cost.

Description

technical field [0001] The invention relates to a continuous production process for preparing glufosinate-ammonium, specifically relates to a process system for synthesizing glufosinate-ammonium by using a continuous Strecker method, and belongs to the technical field of glufosinate-ammonium preparation. Background technique [0002] At present, the synthesis techniques of glufosinate-ammonium mainly include Abzov synthesis method, high-pressure catalytic synthesis method, Gabriel synthesis method and Strecker synthesis method, etc. Because the first three synthesis processes require expensive raw materials and harsh reaction conditions, while the Strecker method is mature, the reaction conditions are not high, and the yield can reach about 35%, which is suitable for industrial production. Therefore, most manufacturers in the world use This method synthesizes glufosinate-ammonium. [0003] The process of synthesizing glufosinate-ammonium by Strecker method is to use triethy...

AI Technical Summary

Problems solved by technology

The operation time of the process is long, the equipment investment is high, the utilization rate is low, and the by-products are not easy to recycle. Since the evaporation is carried out in a single tank, the energy consumption is large, and the recovery of hydrochloric acid is not concentrated, and only less than 20% of dilute acid can be recovered. Environmental pressure Large, high cost and many other problems

[0004] In the existing patent documents related to the synthesis of glufosinate by Strecker method, such as the publication number is CN1267305, the patent name is "method and intermediate for preparing glufosinate" and the publication number is CN103374030A, and the patent name is "a method for preparing glufosinate The invention patent application for the method of ammonium phosphine and the preparation method of its intermediate” only discloses the synthesis process route of glufosinate-ammonium, and does not involve the specific operation process and process equipment of the synthesis process of glufosinate-ammonium. Therefore, based on The present situation of domestic process operation, the present invention proposes a kind of production technique based on the continuous preparation of glufosinate-ammonium of Strecker method

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