X-321
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DMSO separation
Hi everybody,
How could I separate ethyleneglycol from DMSO?
EG bp = 197.3 ºC
DMSO bp = 189 ºC
Thank you.
[Edited on 24-1-2007 by X-321]
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Ozone
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Other relevant physical property:
The melting point for DMSO is 18.5°C and Ethylene glycol melts at -12.9°C.
Give that a shot,
O3
-Anyone who never made a mistake never tried anything new.
--Albert Einstein
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X-321
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Thank you, O3.
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BromicAcid
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The boiling points are fairly close to separation by boiling might be very difficult. However there is an azeotrope between ethylene glycol and
toluene or xylene. This boils lower than ethylene glycol itself, somewhere in the neighborhood of 120ish. This might work to get ride of your
ethylene glycol from the mixture.
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Ozone
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o-xylene, I think. You will also chase out whatever water you may have (and you *will* have some in this mixture, unless you have distilled it with a
Dean-Starke trap onto molecular sieves). But--Have you ever smelled boiling DMSO, expecially if a drop gets into your heating mantle. Good stuff.
Some Data:
Toluene chaser: 110.1°C, but 97.7% of the azeotrope is toluene
o-xylene chaser: 135.7°C, but 93.1% will be xylene.
Following this, It looks like tedious removal of solvent.
Best of luck,
O3
-Anyone who never made a mistake never tried anything new.
--Albert Einstein
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BromicAcid
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Maybe salt it out? DMSO dissolves a number of ionics fairly well and I don't think ethylene glycol compares. Might result in a phase separation and a
simple distillation might give the product?
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Ozone
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@X-321, what proportion of each is present in your mixture, viz. how quantitative does the separation have to be?
O3
-Anyone who never made a mistake never tried anything new.
--Albert Einstein
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X-321
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| Quote: | Originally posted by Ozone
@X-321, what proportion of each is present in your mixture, viz. how quantitative does the separation have to be?
O3 |
1. The molar proportion DMSO/EG = 20/1.
2. Technical grade for EG is ok and the DMSO doesn´t mater since it would be reused many times for the same purpose.
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unionised
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At that ratio freezing the stuff and pouring off the EG (with some loss of DMSO) will work quite nicely. It's also a way to remove water etc from
DMSO, Acetic acid etc
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Ozone
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That's where I was going with the Tm's  . I have not used this method with
ethylene glycol, but have used it to remove, as you say, just about everything else (although, to dry, I still prefer to re-distill over mol sieves
afterwards).
Cheers,
O3
Oh, this can easily be done with an ice-salt bath and a thermometer; no worries.
[Edited on 26-1-2007 by Ozone]
-Anyone who never made a mistake never tried anything new.
--Albert Einstein
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