I am not really quite sure but at this state the addition of hexane or petroleum ether will be good solvent to octanol due to its hydrophobicity then it may be separated as two layers one for octanol-hyrophobic solvent and the other for IL.

I may suggest to use acetone to capture the LI , but it should be carefull with descomposition of LI at temperature

Thank you, Eliseo, that sounds reasonable. Acetone should be relatively easy to get rid of even at room temperature, so I won't apply heat and we'll see.

Have you tried under vacuum? We usually purified ILs from impurities adding activated carbon and allumina at IL+ethylacetate solution and filtrate. I remove organic solvent with rotary evaporator first, then at 120°C and high vacuum ( turbo-molecular pump), but I never deal with such high-boiling organic solvent.. Please read the publication attached for details.

It very much depends on the anion that your IL has. It might be possible to extract or azeotrope the solvent from the IL with water.

Hi Margherita, yes we are using vacuum and we have used an alumina column, but the octanol is still there (no need for analysis, we can smell it).

Thank you, Boyan. The anion is a bistriflate, but the problem with water and octanol is that they form a nice emulsion, so extraction by water is nearly impossible, they wont separate. As for azeotroping, I have little experience with that, but may try.

And thank you, Margherita, for a very interesting paper, it will be useful in more regards, not just the recycling problem.

btw, Margherita, nice paper, I don't want to be a pain in the neck, but there seems to be an error in it, p.A1687, Fig2. The compound depicted is the BETI, not the BTA (or TFSI if you prefer) salt

A naive idea for you. Use polymeric beads of polyvinyl aohol.it may selectively bind octanol. Then it may leave behind

ionic liquid for fractionation.

Or else one need to choose a emulsifier sective for triflate ion then go for ultrafiltratioon

Magdalena, have you tried extraction from DCM/Water?

Short path distilation from film of IL at low pressure can be usefull. We succeded with removal of butyric acid from phosphonium IL. I refer to our papers in attachment.

The second paper is (attachment does not work):

Blahušiak, M., et al., Sep. Purif. Technol., 97 (2012) 186.

I am not really quite sure but at this state the addition of hexane or petroleum ether will be good solvent to octanol due to its hydrophobicity then it may be separated as two layers one for octanol-hyrophobic solvent and the other for IL.

You may try not PVA, but onr of the polymers of Maleic anhydride (usually with another vinyl monomer). It will form a half ester with the polymer and this will scavenge octanol. You need to be in a solvent where the polymer, starting an and product, are insoluble, probably ethyl acetate or CH2Cl2.

Have you tried with steam distillation? Using vacuum of course.

You can do it adding water to the IL and distillating under vacuum

Wow, such a host of ideas! Thank you all! For starters, repeated washing with ethylacetate seems to work, so I'll let you know. I'll also have a look at the methods you all propose for further reference, everything might come in handy.

Try DCM once to extract

Have you tried to use ethers (esp... dimethoxyethane) ... it could help you...

You can see this information in 'The distillation and volatility of ionic liquids' of Earle et al (2006), published by Nature.

You can simply use rotary vacuum evaporator at temperature below decomposition of IL. Use as low pressure as possible with your vacuum pump. It is important to have thin film on wall of rotating bulb what helps to decrease difusion resistance in viscous IL. You can use advantage that most ILs have practically zero vapour pressure. IL will be in residuum and octanol and eventualy water when present will evaporate.