Iminodiacetic acid energy saving cleaning production method

Abstract

The invention discloses an iminodiacetic acid energy saving cleaning production method which comprises the following steps: 1) an iminodiacetic acid saline solution as a raw material enters into a bipolar membrane electrodialysis system for bipolar membrane electrodialysis treatment, the salt room pH is controlled within 3-4 to obtain an iminodiacetic acid salt and iminodiacetic acid mixed solution, and an alkaline solution is obtained in an alkali room; 2) an acid is added into the iminodiacetic acid salt and iminodiacetic acid mixed solution obtained in the step 1) for acidizing to the pH of 2-2.5; 3) an iminodiacetic acid and inorganic salt mixed solution obtained in the step 2) is separated and purified to respectively obtain iminodiacetic acid and an inorganic salt. According to the method, dilution is not needed, the formation quantity of the inorganic salt can be reduced by about 70%, the power consumption is greatly reduced, and the best economic benefit is achieved. In addition, an iminodiacetonitrile reaction liquid is directly used as a staring raw material, so that complex purification process of iminodiacetonitrile can be avoided.

Description

technical field [0001] The invention relates to a production method of an organic acid, in particular to an energy-saving and clean production method of iminodiacetic acid. Background technique [0002] Iminodiacetic acid, CAS No. 142-73-4, abbreviated as IDA, is an important chemical intermediate, widely used in pesticides, medicines, rubber, heavy metal complexing agents, etc., mainly used for the synthesis of glyphosate (glyphosate), etc. Pesticide intermediates, but also used in complexing agents, cleaning agents, stabilizers and surfactants. [0003] The industrial production routes of iminodiacetic acid include iminodiacetonitrile hydrolysis method and diethanolamine dehydrogenation method. Since domestic diethanolamine relies on imports, the price fluctuates greatly, so iminodiacetic acid is produced from iminodiacetonitrile to produce glyphosate Has become the domestic mainstream route. But, existing iminodiacetic acid industrial production method has following tw...

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

Images