Sciencemadness Discussion Board

Making white P on Youtube: how does this work ?

metalresearcher - 30-9-2017 at 07:32

I found a rather easy method to make white P4 using NaPO3 (metaphosphate), SiO2 and Al powder and some table salt NaCl.

https://www.youtube.com/watch?v=mhFyVDBmDVk

How does the reaction work ? Presumably the Al reduces the phosphate to P4, but what does the SiO2 do ?

Σldritch - 30-9-2017 at 07:44

The "ideal" reaction is: 12 NaPO3 + 6 SiO2 + 20 Al = 3 P4 + 10 Al2O3 + 6 Na2SiO3 but it is probably a mixture of sodium silicate and sodium aluminate. The sodium chloride is the flux.

metalresearcher - 30-9-2017 at 11:00

Quote: Originally posted by Σldritch  
The "ideal" reaction is: 12 NaPO3 + 6 SiO2 + 20 Al = 3 P4 + 10 Al2O3 + 6 Na2SiO3 but it is probably a mixture of sodium silicate and sodium aluminate. The sodium chloride is the flux.


Thanks.
I want to replicate it with Ca3(PO4)2 (Ca orthophosphate) whuch should be possible,

UC235 - 30-9-2017 at 18:10

Quote: Originally posted by metalresearcher  
Quote: Originally posted by Σldritch  
The "ideal" reaction is: 12 NaPO3 + 6 SiO2 + 20 Al = 3 P4 + 10 Al2O3 + 6 Na2SiO3 but it is probably a mixture of sodium silicate and sodium aluminate. The sodium chloride is the flux.


Thanks.
I want to replicate it with Ca3(PO4)2 (Ca orthophosphate) whuch should be possible,


Possibly if you ball mill it together, but the ability of the metaphosphate to melt likely ensures good contact between the reactants.