Sciencemadness Discussion Board

Phenol crystals

maldi-tof - 2-2-2020 at 07:17

Hi,

Recently, I have distilled some phenol in order to purify it, and also see how my new rotary evaporator works.
Aside of the pink colour of the distilled phenol (possible oxidation I've read), what surprised me is that I expected some crystals after solidification, but what I obtained is a mass or block of phenol.

Phenol I used as raw material has an aspect of beautiful colorless crystals (comercial name is Crystallyzed phenol), but I haven't been able to obtain it in that kind of form.

Any ideas how to obtain phenol crystals after distillation? I should say that it is one of my first organic projects of my own...

Thank you!

UC235 - 2-2-2020 at 08:27

If it cools quickly, it won't form any sort of crystals. If cooled slowly, you should get at least some attractive needles on top. Just crush it and store it. It's all the same. Trying to manipulate it further will just cost recovery. It will eventually sublime into nice crystals in the bottle.

maldi-tof - 3-2-2020 at 13:28

I'll try cooling It down slowly.

Thanks!!

Tsjerk - 3-2-2020 at 14:08

It melts at 41, shouldn't you want a solid? I would expect a solid chunk of whitish solid in the receiver. The pink is oxidation indeed. Phenols and anilines are prone to oxidation.

maldi-tof - 5-2-2020 at 13:49

Quote: Originally posted by Tsjerk  
It melts at 41, shouldn't you want a solid? I would expect a solid chunk of whitish solid in the receiver. The pink is oxidation indeed. Phenols and anilines are prone to oxidation.


Yes, that's what I obtained in the receiver, something not close to be crystalline.
That's my question, how to obtain crystals in the receiver directly from the distillation...

Abromination - 5-2-2020 at 18:21

Quote: Originally posted by maldi-tof  
Quote: Originally posted by Tsjerk  
It melts at 41, shouldn't you want a solid? I would expect a solid chunk of whitish solid in the receiver. The pink is oxidation indeed. Phenols and anilines are prone to oxidation.


Yes, that's what I obtained in the receiver, something not close to be crystalline.
That's my question, how to obtain crystals in the receiver directly from the distillation...

You aren't going to get crystals in any case. Its not a recrystallization process, its a pure substance. It isn’t going to leave you filterable crystals in a liquid, distilled phenol is all the same thing and will form a solid mass no matter what.