Sciencemadness Discussion Board - what's the usual way to make phosphorus? (white, then red from white, then black?)

what's the usual way to make phosphorus? (white, then red from white, then black?)

chemstudent33 - 13-3-2005 at 17:49

please help! i can't find the chemical method of making white phosphorus from phosphate rock. and i can't find the process for making red or black either.. does anyone know of a site that could help me? (i need a citable site for a chemisrty report)

neutrino - 13-3-2005 at 17:52

The production of phosphorus has been discussed ad nauseum on this board, just search for it.

chemstudent33 - 13-3-2005 at 17:53

Quote:

Originally posted by neutrino
The production of phosphorus has been discussed ad nauseum on this board, just search for it.

thanks very much ^^

BromicAcid - 13-3-2005 at 18:38

Because both of my posts on the different allotropes of phosphorus were in the Whimsy section I'll repost here:

Quote:

[1] High vapor pressure at room temperatures, [2] heat at 540 C, [3] heat at 550 C, [4] heat at 600 C, [5] heat at 125 C, [6] heat at 400 C, [7] heat at 550 C, [8] heat at 300 C at 8000 atm, [9] heat at 380 C with Hg or above 250 C at 12 kb, [10] heat at 400 C with Hg for days, [11] heat at 200 C at 12000 atm, [12] heat at 200 C at 15000 atm, [13] heat at 200 C at 12000 atm, [14] reversible trasition 50-100 kb, [15] reversible transition 110 kb, [16] recrystallize from molten Pb, [17] heat a PBr3 solution, [18] reversible transition at 900 C, [19] reversible transition at 1700 C, [20] reversible transition at low pressure, [21] reversible transition at 44.1 C (but can supercool), [22] reversible transition at -77C or +64 Cunder 1200 atm, [23] sublime under vacuum, [24] heat at 220 C at 12 kb, [25] irradiate with UV at -190 C, [26] condensation of P2 vapor at -196 C, [27] heat above -100 C, [28] heat at low pressure, [29] boils at 280 C, [30] heat at 300 C or expose to light or X-rays, [31] melt about 600 C

I don't know the normal way these changes are done in industry, these are just the known ways. Black phosphorus can also be made in small amounts at pressures less then normal in the presence of mercury, this small amount can then be used to seed future batches made in the normal manner to give better yields. I don't know if black phosphorus is avalible commercially.