A kind of energy-saving and clean production method of diglyphosate

Abstract

The invention discloses an energy-saving and clean production method of diglyphosate, which comprises the following steps: 1) using iminodiacetonitrile reaction solution as a raw material, and obtaining an iminodiacetic acid disalt water solution through alkali hydrolysis; 2) iminodiacetic acid di-salt solution; The brine solution enters the bipolar membrane electrodialysis system for bipolar membrane electrodialysis treatment, and the salt chamber controls pH=3.0~4.0 to obtain a mixed solution of iminodiacetic acid monosalt and iminodiacetic acid; 3) iminodiacetic acid monosalt and The mixed solution of iminodiacetic acid is acidified with acid, and then reacted with phosphorous acid and formaldehyde to obtain diphosphonium. The present invention does not need to separate and purify iminodiacetonitrile and iminodiacetic acid, and obtains bisglyphosate through "one-pot cooking", which avoids the loss and discharge of waste water in the purification process of iminodiacetonitrile and iminodiacetic acid, and improves Improve the yield; at the same time, the bipolar membrane electrodialysis treatment method of the present invention does not need to dilute the feed solution, can reduce the amount of inorganic salt generation, and also greatly reduces power consumption.

Description

technical field [0001] The invention relates to a production method of diglyphosate, in particular to an energy-saving and clean production method of diglyphosate. Background technique [0002] Diglyphosate is an intermediate for the preparation of a broad-spectrum herbicide glyphosate. The chemical name of glyphosate is N-phosphonomethylglycine. Its control is very effective, and its sales have gradually increased in recent years. It ranks first among the 50 largest pesticide varieties in the world, with a market size exceeding US$10 billion. It has been registered and widely used in more than 130 countries around the world. [0003] At present, using iminodiacetonitrile as raw material, hydrolysis and acidification with sodium hydroxide to iminodiacetic acid, and then reacting with phosphorous acid and formaldehyde to prepare diglyphosate is the mainstream production process route of diglyphosate. But, there is following defect in existing diglycophosinous industrial prod...

AI Technical Summary

Problems solved by technology

However, since the solubility of iminodiacetic acid in water is only about 3 grams, it is necessary to dilute the disodium salt of iminodiacetic acid in large quantities, resulting in a decrease in the membrane throughput of bipolar membrane electrodialysis and an increase in the demand for the membrane. Increase investment, and the purification of iminodiacetic acid in the later stage needs to distill a lot of water

Furthermore, when bipolar membrane electrodialysis is carried out to iminodiacetic acid disodium salt, the conversion time in the early stage is shorter and the power consumption is lower, and the conversion time in the later stage is longer and the power consumption is higher. Although the direct conversion to iminodiacetic acid is a clean production process, the energy consumption of the whole process is high, so the industrialization of this method is difficult to implement

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