Sciencemadness Discussion Board

Isopropanol Distillation

achem500 - 25-7-2012 at 17:37

This is my third distillation since getting my glassware, and I decided to concentrate some storebought rubbing alcohol. I collected about 150ml of solvent in about 45 minutes.

Is there an entrainer I can use to get a concentration above ~91%? Any help is appreciated.

kristofvagyok - 25-7-2012 at 17:43

Mix it with some anhydrous potassium carbonate what will absorb the water from it.

Or distill it from activated metallic magnesium. Magnesium isopropoxide will form and it will immediately decompose if some water is still present.

Lithium - 25-7-2012 at 23:15

add a drying agent to the liquid, let sit for a day and filter.

some common drying agents:
CuSO4
CaCl2
MgSO4
Na2SO4
K2CO3
Na2CO3

an alternative, if you have any, is to add CaC2 powder to your liquid in the rbf wait until fizzing slows down and stopper. leave for a day or two. now filter to obtaian DRY solvent. if you have impure CaC2, phosphorous and sulfur compounds may be in solution.

Scr0t - 26-7-2012 at 04:32

As has already been covered elsewhere use NaOH (~8g/100ml).
The NaOH will form an aqueous lower layer salting out the IPA which can be separated and then distilled.

https://sciencemadness.org/talk/files.php?pid=163249&aid=8740

[Edited on 26-7-2012 by Scr0t]

achem500 - 26-7-2012 at 14:46

Thanks for the help