Sciencemadness Discussion Board

Using fraction column to concentrate weak H2SO4 without loss?

teslalab2 - 19-1-2016 at 18:40

I bought some car battery acid, and according to the msds is 38% H2SO4 and the rest is distilled water. Do you think It would be worth the time too use a fraction column to concentrate it? I could just boil it until the thermometer reads the boiling point of the azeotrope. I think that could take the guesswork out of boiling it down. This is assuming of course there is no impurities.

I did a google search on this but didn't find anything. Thanks!

Detonationology - 19-1-2016 at 18:52

Simple distillation apparatus or a retort is all that is necessary. Any other glass seems to be delicate at temperatures over 300 degrees C. It's referred too around here as "boiling the bat" by ave369. Check out some her posts first; she is probably the most knowledgable person to ask about this process.

BromicAcid - 19-1-2016 at 19:10

I would be afraid to try that with a fractional column, inevitably material will condense and fall back into the pot, when you get to concentrated acid this can become violent.

teslalab2 - 19-1-2016 at 20:21

Ok thanks for the warnings. The thought of a failure with boiling h2so4 is stuff of nightmares. Thank you all

hissingnoise - 20-1-2016 at 06:01

Quote:
Simple distillation apparatus or a retort is all that is necessary.

(sigh!)To reconcentrate BA simply heat the soln. in a suitable container until dense, white fumes appear!


Atrum - 20-1-2016 at 07:04

I was boiling some conc H2SO4 and a nickel a few days ago to make NiSO4. Small volume. Maybe 20 mL.
Every so often a drop of water that condensed on the watch glass bottom would drip and cause the whole mix to flash boil.

Kinda freaky

[Edited on 1-20-2016 by Atrum]

Deathunter88 - 20-1-2016 at 09:48

Quote: Originally posted by hissingnoise  
Quote:
Simple distillation apparatus or a retort is all that is necessary.

(sigh!)To reconcentrate BA simply heat the soln. in a suitable container until dense, white fumes appear!



But white fumes appear at 70% and it is difficult to judge exactly what the final concentration is. I would say if you have a distillation apparatus then it is better to distill than to simply boil. Otherwise, boiling is tedious but works.