Sciencemadness Discussion Board

purify acetic acid

pbmineral - 5-7-2007 at 02:03

Hi, I've just bought some acetic acid from drugstore
The concentration is around 75%
I'd like to get glacial acetic acid (so purify it).

What can I do ?

- distillation (I have pure H2SO4)

Waiting for your answers


Attachment: Mes réactifs Pierre.xls (28kB)
This file has been downloaded 825 times

unionised - 5-7-2007 at 09:59

I have a feeling this has been discussed before. Did you search first?

garage chemist - 5-7-2007 at 10:28

No, the discussion has always revolved about concentrating vinegar. Here the subject is getting from 75% to 100%, so I think this thread can continue.

Azeotropic removal of the water using a third component like benzene, toluene or ethyl acetate which forms a lower- boiling azeotrope with water is used in industry. Add a good amount of ethyl acetate to your acetic acid, and distill over a column. First fraction is ethyl acetate-water azeotrope, second one is excess ethyl acetate (if you used enogh of it) and third one is acetic acid of at least 99% purity.

Freezing is a method to get the last bit of water out, e.g. to get from above 95% to nearly 100%. Acetic acid and water form an eutectic which freezes below -16°C, so only if the initial concentration of the acid is above this can freezing have any effect.
I dont know the composition of this eutectic though.

bio2 - 5-7-2007 at 15:35

Check one of my old posts on using the urea adduct of >60%
Acetic Acid to get the Glacial.

chemkid - 6-7-2007 at 16:49

What country do you live in? What drug stores do you go to? I've never heard of 75% Acetic acid in drug stores?! Please inform me!

ldm2319 - 25-7-2007 at 08:06

good method !

chemrox - 25-7-2007 at 14:10

I belive the library has a copy. This is from, Perrin, DD & WLF Armarego, Purification of Laboratory Chemicals, 3rd Ed., Butterworth Heinmann, Oxford etc.

[Edited on 25-7-2007 by chemrox]

acetic.jpg - 123kB

pbmineral - 25-7-2007 at 14:16

Hi everybody,
Please excuse me I was too busy to answer your questions and thank you for all your posts.

I live in France in "Rhône Alpes" Here many chemicals are availlable.
All VWR for instance except éthanol or ether
and suppliers for swimming pools just an example :
all chemicals are availlable and cheap !

Thnak you for the images and scans !