NZniceguy - 19-11-2017 at 18:35
Im trying to seperate an acetic acid/acetic anhydride solution by fractionating(fractionation?) and as I lose a bit at the end and am only doing small
amounts 20 to 100mls at a time. What I need is a chaser solvent that has a boiling point higher than 138 degrees C and wont react with the acid or
anhydride..................any suggestions?
clearly_not_atara - 19-11-2017 at 19:05
According to the azeotrope table on Wikipedia, acetic acid forms an azeotrope with toluene in a 72% toluene / 28% AcOH ratio. I think that might help.
Otherwise propylene carbonate has a very high boiling point of 242 C so it's probably fit for the original purpose.
karlos³ - 22-11-2017 at 15:30
Is it AcOH or Ac2O which you have in excess? If the latter, following procedure would be suitable:
add enough acetanhydride to the free acid, to react any water present to additional AcOH, which is the standard method for absolution of acetic acid.