An optimized method for the synthesis of diglyphosate from iminodiacetonitrile

Abstract

The invention discloses a method for synthesizing bisglyphosate from iminodiacetonitrile. The following steps are adopted: firstly, part of the high-concentration liquid alkali is made into a 20%-25% alkali solution, the temperature is raised to 40-60°C, and then slowly Dosing of iminodiacetonitrile, 1-2 hours after the addition, add the remaining amount of liquid alkali during or after the addition of iminodiacetonitrile; raise the temperature to 80-95°C, keep it warm for 1-2 hours, deamination for half an hour , add hydrochloric acid to adjust the pH, and obtain iminodiacetic acid and its sodium salt solution; filter, and react the filtrate with phosphorus trichloride and formaldehyde to generate diglyphosate wet material and waste water. The invention is simple and easy to implement, reduces the water consumption during alkaline hydrolysis, saves the alkaline hydrolysis dehydration process, improves the deammonization efficiency, reduces energy consumption, increases the content of iminodiacetic acid, improves the yield of diglyphosate, and has the advantages of Higher economic benefit.

Description

technical field [0001] The invention relates to a method for synthesizing diglyphosate from iminodiacetonitrile, in particular to a production method for synthesizing diglyphosate by reducing energy consumption and improving production capacity. Background technique [0002] The iminodiacetic acid (IDA) method was developed in the late 1990s and realized industrialized production. The iminodiacetonitrile method (IDAN) is mainly used in this process in China. Due to the advantages of cheap and easy-to-obtain raw materials such as iminodiacetonitrile, good catalyst selectivity and higher yield for glyphosate oxidation, the production cost is lower, and the degree of cleaner production is higher than that of the glycine method. Mainstream technology. [0003] In the route of synthesizing bis-glyphosate by iminodiacetonitrile now, iminodiacetonitrile all is to carry out alkaline hydrolysis in dilute lye (alkali content about 20%), after alkaline hydrolysis is finished, first de...

AI Technical Summary

Problems solved by technology

This route needs to control the lye concentration at about 20% during the alkaline hydrolysis process, so a large amount of water must be poured into the liquid caustic soda to dilute the liquid caustic soda, but high-quality synthetic diglyphosate requires IDA concentration at 25% Above, so methods such as evaporation should be adopted to remove part of the water in the system after the alkali hydrolysis is completed, and the amount of dehydrated water is at least 40%-50% of the amount of water added, and dehydration takes up a lot of time, so in terms of energy consumption and There are major disadvantages in terms of production capacity

In terms of process route optimization, relevant research units and production companies have conducted a lot of research, but there are few studies and reports on reducing the cost of diglyphosate from the perspective of reducing energy consumption and increasing production capacity in the alkaline hydrolysis process