Use of an alembic for WP production, violet/hittorfs P?
For production of white phosphorus, stating from red P has anyone used an alembic, in the fashion of the old style alchemists?
I have a 500ml retord, with a relatively short exit tube.
Could a short stiff length of wide-bore plastic tubing be used to extend the length of the glass exit tube of the alembic in order to pass the P4
vapor into hot water in order to condense the WP? if not, the alembic outlet can simply be placed into hot water, and wrapped in Al foil to insulate
the outlet tube.
The retort itself of course will be purged with argon, until Ar bubbles out of the water in the collection beaker in order to avoid ignition of the P.
Also, violet phosphorus is one of the top of my 'to do' list items. Question-are 'violet phosphorus' as prepared by heating red P in vacuo and
sublimation of crystals of violet P different from 'hittorf's phosphorus, prepared by melting lead (can Pb alloys, like the lower melting lead solder
be used? my proposed route is to cast a mold out of Pb, and cover with fine lead shavings or thin turnings, powder etc. which then can be fused
quickly, followed by pouring molten lead over the top.
Or, alternatively, simply preparing a mold in which the crystal of violet P is to be made, filling it with phosphorus under argon and pouring molten
lead over it sufficient to provide a protective layer of Pb over the top.
Wikipedia also mentions the existence of a fibrous form, but gives no references whatsoever. Anybody know anything about either it, or vitrified grey
phosphorus? I seem to recall a phase diagram of allotropic modifications of elemental phosphorus and the corresponding procedures with which to
prepare them. For some reason, vitreous P sounds particularly intriguing.
Now, question-Presumably under the molten lead, white phosphorus is formed under the heating. So rather than using powdered red P, and presumably
getting back multiple smaller crystals of Hittorf's violet phosphorus, will filling the mold with cast white P sufficient to fill it, before topping
off with molten lead suffice?
And lastly, whilst I can order some, I have no HNO3 or nitrates with which to prepare some. Will either HCl/H2O2 or peroxide/phosphoric acid suffice
to dissolve the lead? and my reading states a prolonged heating is required, 24 hours should suffice, should it not?
What I'm aiming for with the violet (Hittorf's) phosphorus is to grow decent sized single crystals, rather than the chunks and grains that was on
offer on ebay for a short time, the one time I've seen violet P properly was the photos there, and it was on offer in the form of small crystalline
chunks. Is it possible to grow larger, good quality crystals.
Lastly, what is the transition temperature from white to red? I've done it on a small scale, using a micro-torch and test tubes, to produce a small
quantity. This time, having more red P at my disposal, (sigma, afaik) so of good quality, I'm aiming for a couple of hundred grams of white P,
condense in hot H2O followed by heating in a dichromate/conc. H2SO4 bath, to remove the oxides, and under argon, remelting under H2O.
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