Sulaiman
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Conversion and/or Separation of Red+White Phosphorus
I bought 25g of red phosphorus to make some P2O5 dessicant,
then got lazy and bought 100g of P2O5 via ebay, (also cheaper than synthesis)
so I now have spare red phosphorus.
I am considering obtaining a little white phosphorus from the red,
just enough to test/play/dispose. (No safety lectures reqd.)
I found endless references for white-to-red
Googling red phosphorous to white gave plenty of hits; most for white-to-red or irrelevant
and lots on 'meth' sites that I do not want to have an unnecessarily large history of visiting.
One method that I am considering is using a solvent to dissolve any un-polymerised P4 (white phosphorous) out of the red.
I found some references for the solubility of white but almost nothing for red.
So far ethanol seems a possibility due to mentions of insolubility of red and data (0.208 g/100ml) for white.
1) could anyone point me towards solubility tables for red Phosphorous in various solvents?
or
2) is there a known commonly available solvent that dissolves white but not red phosphorous ?
3) I could not find any reference for a simple (not via several intermediate compounds) method for converting red to white phosphorous,
any suggestions ?
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Detonationology
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I have no practical experience with elemental phosphorus, but I have heard that white phosphorus is very soluble in carbon disulfide.
“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
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Sulaiman
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so is red 
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Detonationology
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Have you checked out this thread? Not much info, but it's some
[Edited on 10-13-2015 by Detonationology]
“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
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Magpie
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Chloroform, CCl4, benzene, and hexane are solvents for WP. I'm guessing that they do not dissolve red P.
Dichloromethane might work also.
Quote: Originally posted by Sulaiman  |
3) I could not find any reference for a simple (not via several intermediate compounds) method for converting red to white phosphorous,
any suggestions ?
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Pyro converted some red P to white P. Not without adventure, however. 
[Edited on 13-10-2015 by Magpie]
The single most important condition for a successful synthesis is good mixing - Nicodem
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Sulaiman
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Detonationology,
... my appologies, just been re-reading the phosphorus section of
A TEXT-BOOK OF INORGANIC CHEMISTRY. J. NEWTON FKIEND, VOLUME VI., PART II. PHOSPHORUS.
I found this
"The red phosphorus prepared by moderate heating may be ground
up with a solution of sodium hydroxide as in the technical preparation
(see p. 10) and may also be extracted with carbon disulphide until
the extract is free from white phosphorus. The resulting preparation
is considered to be the purest red phosphorus."
.............................................................................................
Magpie, thanks,
even though red P is insoluble compared to white P in many solvents,
I am expecting trace amounts of white P in my existing commercial grade red P (or maybe none?)
so I'm looking for a solvent for white P in which red P is truly insoluble to have any chance of success - I guess
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