In the preparation process of glyphosate, an intermediate in the synthesis of glyphosate, either the diethanolamine method or the iminodiacetonitrile method can be used, both of which can achieve the purpose of preparation. However, no matter which method is adopted, a large amount of waste water will be produced. If it is directly discharged, it will not only cause waste of chemical elements (substances) and water resources, but also have adverse effects on the environment. Therefore, after the preparation is completed, the wastewater needs to be treated in an appropriate way to extract valuable chemical elements (substances) therein, and then recycle the water resources.
A process of wastewater treatment process in the preparation process of glyphosate synthesis intermediate glyphosate
A new process for waste water treatment in the preparation process of glyphosate synthesis intermediate glyphosate, in the process of wastewater treatment, sodium chloride and glyphosate can be recovered, and the remaining water can also be recycled, realizing the purpose of environmental protection. As far as the wastewater treatment process is concerned, the specific process is as follows:
① Use ammonia water or sodium hydroxide to adjust the pH value of the bisphosphonate solution to between 2 and 7, and use one of a precision filter, a bag filter, and a filter press to remove the adjusted glyphosate solution. The solids present are then removed using an activated carbon multi-media filter to remove the viscous liquid present in the solution. On this basis, a filter membrane with a pore size of 1 micron to 50 microns is used to remove the particles present in the solution, and finally the solution is put into the tank of the raw material solution, so that the light side can enter the secondary membrane system. middle.
②In the secondary membrane system, the glyphosate solution will be divided into two parts. Among them, the light side part will directly enter the tertiary membrane system, while the concentration test contains a large amount of bisphosphonates, which will return to the inlet position of the equipment at this time. When the mass fraction reaches 5% to 12%, this part will be The concentrate is placed in the reservoir numbered 1.
③In the tertiary membrane, the bisphosphonate solution will also be divided into two parts, and the concentrated solution will be directly returned to the outlet in the secondary membrane system. The solution on the light side contains more sodium chloride and will be collected in in reservoir number 2.
④In the storage tank numbered 1, the concentrated solution will be mixed with deionized water and bisphosphonate solid, and at the same time, glyphosate will be generated after oxidation treatment. In the liquid storage tank numbered 2, because the solution has been treated by membrane, sodium chloride and chlor-alkali can be extracted after treatment, and the remaining water can be recycled and reused.
Application of wastewater treatment technology in the preparation process of glyphosate synthesis intermediate glyphosate
Combined with the process of wastewater treatment in the preparation process of the above-mentioned glyphosate synthesis intermediate, glyphosate, this process can be directly applied in practice. Specifically, in the process of preparing glyphosate, 10,000 kg of mother liquor was produced, and this part of the mother liquor was directly added to the reaction kettle, and the pH value of the mother liquor was adjusted with sodium hydroxide to ensure the final acidity The base number is equal to 2.0. Use a precision filter to process the mother liquor, and then put it into the raw material box. At this time, the standard of 20 meters head must be used, and the bisphosphonate mother liquor is injected into the multi-media filter, so as to remove the viscous liquid in the mother liquor. , and then use a filter membrane with a pore size equal to 50 microns to filter and process the micron particles present in the mother liquor.
On this basis, the treated mother liquor is divided into two parts using an ultrafiltration membrane, the solution on the light side will enter the secondary membrane system, and the concentrated solution will be automatically returned to the raw material tank. In the secondary membrane system, the bisphosphonate mother liquor will also be divided into two parts, and the concentrated test solution will return to the inlet. In tank 1, the total amount is equal to 4000 kg. At the same time, the light side solution will enter the tertiary membrane system under the condition of 100 meters head, and it will also be divided into two parts. Will be stored in Reservoir 2, totaling 6000 kg.
A part (800 kg) of the 4000 kg solution in the No. 1 liquid storage tank was added to the glass-lined reaction kettle, and the equipment was started to stir. During this process, deionized water (500 kg), solids with a mass fraction of bisphosphonate equal to 90% (1110 kg), and sodium tungstate (3 kg) were added in sequence, and stirred uniformly, while the temperature was adjusted To 60 degrees Celsius, 720 kg of hydrogen peroxide with a concentration of 28% was slowly added to it, and the temperature was maintained for 30 minutes. After that, the temperature was adjusted to 25 degrees Celsius, 100 kg of ferric nitrite was slowly added to the liquid, and then allowed to cool and crystallize naturally. After drying the crystals, 610 kg of glyphosate with a mass fraction of 95% can be obtained, and 2500 kg of a glyphosate filtrate with a mass fraction of 3.8%. At the same time, after concentration, 940 kg of glyphosate water can be obtained.
To sum up, a new process for waste water treatment in the preparation process of glyphosate synthesis intermediate, glyphosate, is relatively simple in the overall process, has strong operability, and can provide a lot of convenience for staff. . On this basis, the application of this new wastewater treatment process in practice can reduce the difficulty of wastewater treatment, improve the efficiency of chemical element (substance) recovery, and at the same time fulfill the basic goal of saving water resources. Therefore, combined with the analysis in this paper, it is found that a new process for wastewater treatment in the preparation of glyphosate, an intermediate in the synthesis of glyphosate, has strong feasibility.