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Tsjerk
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Okay sorry, I indeed didn't read your post carefully and didn't think freezing 15% (if 100% efficient) from 75% was worth the trouble. next time I
will try to assume a bit less.
What you have, both the 60% and the 75% is already quite concentrated. I would indeed suggest using some drying agent like Na2SO4 or MgSO4, decant or
filter and then freeze. Molecular sieves will dissolve in acid.
If you don't have anhydrous salts but do have an oven you can bake the water out of both sodium and magnesium sulfate. When you start with low
temperatures and slowly go up you can prevent the salts dissolving in their own water, thereby keeping the surface area high making the process
faster. Microwaving the salts is faster but I can imagine larger amounts to be hard to microwave.
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Yes, I have MagSulf. My goal is to produce GAA, so those 15% is indeed of importance.
I'll try the freezing of a little bit larger quantities first, just need to get a new burette for titration. My old one broke. Decanting off and
saving the 60% for subsequent distillation trials.
Thank you!
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Fery
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here I found well explained process of freezing a mixture of acetic acid + water:
https://chemistry.stackexchange.com/questions/2506/acetic-ac...
eutectic point is at -27 C for 88,3 wt% acetic acid
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I actually left this project. Gave up and ordered some GAA from the ultraprofessional Chemship1978.
But that was the link I shared in one of my earlier posts. For me, it quite boldly says what Tsjerk was trying to tell me: that concentration above
the eutectic point is not possible through fractional freezing. In any case, it's too much work for me.
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