Was just thinking about rinsing away residual mother liquor again and got an idea.
Non-polar solvents with low water solubility seem preferable during extraction for avoiding water-based contaminants. But for recrystallizations, what if you chose a non-polar solvent with some water miscibility, dried it completely before use, then used that property to rinse away the residual mother liquor with alkaline water?
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Seems like diethyl ether, ethyl acetate, and 1-butanol would be suitable for alkaline water rinsing. Then the residual solvent to evaporate would be 99% water and not dissolving or depositing DMT as it does so. Then maybe some distilled water rinses to follow the alkaline rinse, to reduce trace base deposition in exchange for some trace DMT carbonate deposition?
I guess diethyl ether might be an ideal solvent to separate; since it has the lowest surface tension, pouring it off the crystals should result in the least amount of residual, reducing the amount of water it would require to dissolve the residual. Then any trace remaining after the rinses would be most likely to fully evaporate with such a high vapor pressure. It also has the highest DMT solubility, though, so the crystals would be more sensitive to thermal changes, and the evaporated residual could deposit more DMT per volume than the other solvents.
Problem is the high DMT solubility of those solvents make them unviable for freeze precipitation. So the crystals would first have to be precipitated another way, perhaps antisolvent methods. I've seen
@benzyme mention dropping n-heptane into diethyl ether. Or 1-butanol's low vapor pressure could make vapor diffusion possible, with an alkane precipitator. But since alkanes have lower water solubility, idk how well the residual mixtures might dissolve in water.
And what happens to the DMT dissolved in diethyl ether when rinsed with water that dissolves some of the diethyl ether? Does DMT go with the diethyl ether into aqueous solution? Or would it precipitate the same as if the diethyl ether were evaporating?