Sciencemadness Discussion Board

Cinnamaldehyde azeotrope with ethanol?

OneEyedPyro - 13-3-2019 at 17:04

An uncle of mine recently passed away and left behind a bunch stuff and I've been tasked with removing whatever property that his kids didn't already take, I found a couple cases of fireball whiskey that apparently nobody wanted.

I'm not a big fan of fireball but I figured I could extract the ethanol and use it for recrystallizations or something, unfortunately the cinnamon flavoring is coming over with the ethanol during distillation.

Any ideas on how I could overcome this without going to too much trouble?

clearly_not_atara - 13-3-2019 at 18:03

It simply happens that the human nose is extremely sensitive to cinnamaldehyde. Some contaminants are always carried over in distillation because all compounds have a positive vapor pressure. I suppose you could remove it as the bisulfite adduct, but for all practical purposes, redistilling should be enough.

fusso - 14-3-2019 at 07:03

Oxidize aldehyde with Benedict/Fehling solution and remove cinammate salt? Not sure if this work on conjugated aldehydes.

OneEyedPyro - 17-3-2019 at 17:21

It definitely wasn't a small amount coming over. The distillate had a yellow tinge and an extremely strong smell/taste of cinnamon, seemingly even more so than the whiskey itself but that might just be due to the alcohol concentration being much higher.

I already have several gallons of methanol which works as well or better than ethanol for anything I might need an alcohol solvent for, it wouldn't make sense to go to any more trouble to purify it.
I think I'll just hang on to it until I find somebody who likes Fireball.

UC235 - 17-3-2019 at 19:42

Volatile compounds co-distill even if they don't azeotrope. It's why steam distillation works on all sorts of compounds. If they're even kinda volatile, they have a partial pressure at the boiling point of the carrier solvent and will get carried over. Your options are basically to fractionally distill the stuff with a good column or try to chemically destroy it. I wouldn't suggest NaOH though, since that is shown elsewhere on this forum to produce acetaldehyde and benzaldehyde through a retro-aldol.