Sciencemadness Discussion Board

Questionable Synth:Sodium Metasilicate

Volitox Ignis - 31-1-2016 at 10:43

I have been looking around on the Internet for any information on how to make white phosphorus (I've never seen it burn firsthand,only on video),and stumbled across this video:
https://www.youtube.com/watch?v=mibM4WUx74Q and parts two and three. Firstly,I think that the amounts of each chemical were not stoichiometric,but that is not my main concern.
I believe that the reaction occurring during the process to be:
24 Al + 2(NaPO3)6 --> 12 Al2O3 + 3 P4 + 12 Na

Since sodium reacts with water to produce sodium hydroxide,which can react with the phosphorus to produce toxic phosphine gas,this method is very dangerous. I then thought that the sand added to the salt/sodium hexametaphosphate/aluminum reacts with the sodium and hexametaphosphate to produce sodium metasilicate,thus preventing the production of phosphine. Are my assumptions correct? If so,what is the equation for the reaction that produces sodium metasilicate?

Yes,I read the replies to my propellants thread,thanks for the help!



[Edited on 31-1-2016 by Volitox Ignis]

blogfast25 - 31-1-2016 at 11:15

You'll find the answers in the sticky phosphorus thread.

BromicAcid - 31-1-2016 at 12:40

Start by reading my primer:

https://www.sciencemadness.org/whisper/viewthread.php?tid=20...

Spoiler Alert - See Sodium Aluminate

[Edited on 1/31/2016 by BromicAcid]

Volitox Ignis - 31-1-2016 at 13:21

After reading around on the Phosphorus thread and some reworking, the equation came out as:
2 (NaPO3)6+ 20 Al + 6 SiO2 --> 6 Na2SiO3 + 10 Al2O3 + 3 P4
-From BromicAcid's PDF

Assuming no losses,this should result in a 30% yield of phosphorus based on sodium hexametaphosphate, am I right?

[Edited on 31-1-2016 by Volitox Ignis]

[Edited on 1-2-2016 by Volitox Ignis]

blogfast25 - 31-1-2016 at 15:11

Quote: Originally posted by Volitox Ignis  
After reading around on the Phosphorus thread and some reworking, the equation came out as:
2 (NaPO3)6+ 20 Al + 6 SiO2 --> 6 Na2SiO3 + 10 Al2O3 + 3 P4
-From BromicAcid's PDF

Assuming no losses,this should result in a 39% yield based on sodium hexametaphosphate, am I right?



Yield of what?

Volitox Ignis - 31-1-2016 at 15:28

Quote: Originally posted by blogfast25  
Quote: Originally posted by Volitox Ignis  
After reading around on the Phosphorus thread and some reworking, the equation came out as:
2 (NaPO3)6+ 20 Al + 6 SiO2 --> 6 Na2SiO3 + 10 Al2O3 + 3 P4
-From BromicAcid's PDF

Assuming no losses,this should result in a 39% yield based on sodium hexametaphosphate, am I right?



Yield of what?


Ah,sorry for not writing it: 30% yield of phosphorus. I fixed my post now.

[Edited on 31-1-2016 by Volitox Ignis]

[Edited on 1-2-2016 by Volitox Ignis]

BromicAcid - 31-1-2016 at 16:14

Reaction scheme is balanced, check.

The reaction of 2 mols of sodium hexametaphosphate (1223.54 g) should yield 3 mol of P4 (the exact allotrope does not matter, as distilling you will get P2 as well, molecular weight either way is 371.64 g).

371.64 g phosphorus / 1223.54 g sodium hexametaphosphate x 100 = 30.37%

Is that what you are going for? Essentially if all your phosphorus is available you're hexametaphosphate is 30.37% phosphorus by weight which would be the maximum theoretical yield (in practice it is about half of that IIRC). Versus your reaction mixture, your reaction mixture should give a 18.54% mass yield of phosphorus.

blogfast25 - 31-1-2016 at 16:17

Sodium hexametaphosphate contains 30.4 w% of P. Is that what you mean?

To calculate an actual reaction yield you would need to know how much P was obtained from how much sodium hexametaphosphate.

[Edited on 1-2-2016 by blogfast25]