Cou - 25-11-2019 at 10:23
I followed Nile Red's procedure at https://www.youtube.com/watch?v=Q_f1hRmhUX8, which in turn comes from an unintentional chaos prepublication at https://www.sciencemadness.org/whisper/viewthread.php?tid=27...
I insulated the 500 mL RBF with aluminum foil, but the distillation failed because phenol vapors could not get high enough to distill over. The vapors
were exactly 181 F, the boiling point of phenol. I waited a long time for the vapors to warm up the adapter, but they just kept refluxing back down
and eventually all formed side products in RBF so nothing was refluxing anymore. https://gfycat.com/disguisedblushinghousefly
According to Nile Red, we use a 500 mL RBF, even when the salicylic acid could fit in a 250 mL RBF, because it works as a pseudo fractionating column
to keep out side products and salicylic acid vapor.
I was considering using a 250 mL RBF to avoid this next time, but maybe I just need to wrap the flask AND the distillation adapter with cotton balls
and aluminum foil?
Anyway, the lesson here is that using aluminum foil isn't sufficient insulation, and you may need to insulate the adapter too. It's also possible i
was heating too much; prepublication says the distillation could take hours.
[Edited on 25-11-2019 by Cou]