Sciencemadness Discussion Board

ethanol recovery

shadow - 27-6-2016 at 08:18

I just cleaned out a gas tank with phosphoric acid, rinsed with ethanol, then acetone.
The rinsings went into 3 different containers with the majority of each component in each container
I was going to chuck it all away but decided to distill it all down to recover the original components.(over 3 gallons).
I got the acetone off easily, but when I started heating the second container,(phosphoric acid washings with mosty ethanol), the stopper on the heating vessel popped off.
Some liquid had already come over at that point but didn't smell like clean ethanol.
I suspected that a reaction occured in the heating flask, and found out that ethanol and phosphoric acid do react but was unable find what the product is supposed to be.
Does anyone know what that product is?
I'm using a temperature controled vigruex condenser, so the separations should be reasonably complete.
Thanks ahead,
Gc

myristicinaldehyde - 27-6-2016 at 12:59

Possibly an ester formed to make triethyl phosphite. Although that seems very unlikely to me.
Or, the acid catalyzed the formation of the acetal or hemiacetal. This seems more likely to me.

Since both are equilibrium so maybe the heat allowed for just enough to form, and they are both odorous
How does it smell?
Edits: spalengg

[Edited on 2016-6-27 by myristicinaldehyde]

Melgar - 5-7-2016 at 13:47

Does it smell like starting fluid? If so, you probably got diethyl ether, since that would have the lowest boiling point of all the possible products, I think.