The effect of acetamiprid mother liquor on synthesis
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Our company produces imidacloprid technical material. I would like to ask whether the continuous use of imidacloprid mother liquor affects the synthesis yield of imidacloprid; the mother liquor mainly contains toluene, a small amount of methylamine salts, cyanoethyl ester, etc
Continuous application will definitely increase the yield, but it will also inevitably lead to an increase in impurities. There shouldn’t be toluene in the mother liquor, right?
Reply to 2#: I’m a primary school student. Toluene remains from the previous step of solvent removal; my yield is actually decreasing instead of increasing, and I’m stuck
There are several reasons why you need to verify whether the amounts of materials used in the previous process – namely, the amount of acetamiprid used in its synthesis – are sufficient, whether there is enough cyanoethyl ester available, and how many times the mother liquor can be reused Is the crystallization complete? Once that’s resolved, I believe there should be no problems!
Reply to 4#: I’m a primary school student. The amount of material used is sufficient, and there’s enough ethyl ester as well. The mother liquor was used only once, and the centrifugation temperature was reduced below 0 degrees Celsius; nothing seems to be wrong with these aspects. But the wet powder just won’t come out
Maybe the temperature of the drop addition was incorrect, or there were issues with crystallization, such as the choice of solvent!
Reply to 6#: I’m a primary school student. Does increasing the temperature affect the reaction? I add the ethyl ester without controlling the flow rate; the reaction temperature ranges from 30 to 50 degrees, and ethanol is used as the solvent. If it’s the temperature that’s the issue, then what range should my temperature be kept within? Thank you
Ethanol should not be suitable for synthesis; it is recommended to remove ethanol and use an inert solvent instead!
Is there material leakage during centrifugation? Is the cooling rate well controlled?