TheMrbunGee
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Ammonium thiocyanate solubility for purifying
Hey SM,
I have some old Ammonium thiocyanate, about 200g, but it is really dirty stuff, and looks orange-ish. I was going to clean it up, but water as a
solvent would be bad for recovery due to high solubility even in low temperatures and I could not find free info on solubility in other solvents.
(other than "very soluble" and "slightly soluble", which gives me nothing.)
Might you have some charts on solubility in acetone or other solvents like MeOH, EtOH, or something else, which could help me with recrystallization?
Thanks!
[Edited on 15-9-2018 by TheMrbunGee]
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Sulaiman
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As no one seems able to help with data
with a few test tube scale experiments you can determine the approximate hot/cold solubilities,
or the suitability of the solvents for re-crystallisation, yourself 
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unionised
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I'd try a mixture of ethanol and water. It often seems to work for very soluble salts.
The exact "recipe" is determined- as Sulaiman says- by experiments in test tubes.
Be careful not to set the place alight.
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TheMrbunGee
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Ok, thanks, looks like I'm gonna have to do that..
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S.C. Wack
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http://gen.lib.rus.ec
http://bookfi.net
http://b-ok.xyz
https://archive.org
"Purification of Laboratory Chemicals"
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TheMrbunGee
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hey, this was actually helpful, Thank you, gonna save this for future purifications.
Shame I already used 93% ethanol, in which it dissolves at 52g/100ml @ ~70°C. solution is now sitting in thermos, crystallizing for 13th hour now,
loosing about 3°C/hour.
(Acetone also did about 50g/100ml @ ~65°C, but impurities or Ammonium thiocyanate itself slowly reacts with or catalyzes acetone. And it was hard to
separate crystals, got about 20g from 50g )
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S.C. Wack
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The suggestion there for acetonitrile seems perfectly reasonable, given the entry in the Merck Index, which indicates a need for a fairly polar solvent. If methanol doesn't work I would think mixtures with ethyl acetate would.
PS DCM and something would also be interesting. Things like soluble in this and not in that can be very helpful. The Merck gives a good mental picture
of a polarity boundary here.
[Edited on 18-9-2018 by S.C. Wack]
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