crestind
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Can Azeotropes Be Separated/Broken By Fractional Freezing?
Only see talk about the BPs. Never the freezing point.
[Edited on 16-8-2021 by crestind]
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unionised
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"Can Azeotropes Be Separated/Broken By Fractional Freezing?"
Usually.
You would be unlucky if the eutectic composition was the same as the azeotropic one.
You can also break azeotropes by distillation at a different pressure.
You can also sometimes separate them by adding an involatile solute. The azeotropic concentration of alcohol and water will be different from that for
a mixture of alcohol, water and sugar or salt.
It may not be very different.
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macckone
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Fractional freezing is common in purification of acetic acid in the home lab and hydrogen peroxide on an industrical scale.
Fractional freezing of alcohol is used to make beer concentrates in places with very cold temperatures.
Fractional freezing can be used in benzene purification.
One of the problems with fractional freezing is you usually have to separate a small amount of liquid from a large quantity of crystals.
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MadHatter
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Freezing Alcohol
I agree with fractional freezing for some separations. It works
reasonably well with ethanol made from fruity sugar mixes
but I wouldn't try that with a corn mash. It would still taste
nasty. My case is applejack. Usually fermented with a high
alcohol yielding yeast. After the yeast settles out, freeze and
separate the liquid from the frozen mixture as quickly as
possible. The proof can be moderately high. On a side note this
is a legal alternative to distillation.
From opening of NCIS New Orleans - It goes a BOOM ! BOOM ! BOOM ! MUHAHAHAHAHAHAHA !
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