Sciencemadness Discussion Board

a question

osamafon - 30-1-2003 at 16:28

a ruschen book says that petn´s explosive energi is 5,9KJ/kg and rdx´s is 5,45 KJ/kg so as hmx why is petn not more powerful powerful then hmx??? I read that hmx´s densyti is 1,91 g/cm3 and petn´s 1,77 g/cm3

KABOOOM(pyrojustforfun) - 30-1-2003 at 20:14

energy released from an ordinary flash is 8.989 does it mean it's more powerful than HMX?! :P energy is not the only factor of power, volume of gas and Vod influence the power. I have The Chemistry of explosives (by Akhavan jacqueline) it has some formulas for caculating power of explosives. later I may bring some of the formulas.

osamafon - 22-3-2003 at 22:40

can I synt. petn with 58%HNO3 and H2S2O7. I read that it can`t synt. with mixed acids

Microtek - 23-3-2003 at 03:15

Mixed acids work just fine, as does H2SO4 + alkali metal nitrate though the yield suffers. You don't need pyrosulfuric acid, ordinary 96% works fine.
I think the reason you might think it doesn't work, is that the product from mixed acid synthesis is more difficult to purify; small amounts of sulfuric acid is trapped inside the crystals and can't be washed away. This is not a problem however, as PETN is so soluble in acetone, so a simple neutralization of the acetone soln and precipitation with water makes it very pure.

rikkitikkitavi - 23-3-2003 at 04:27

xoo, that might not work, since you dont have SO4- ions in a concentrated sulfuric acid, but only HSO4-

H2SO4 + (SO4)2- = 2 HSO4-

and sodium bisulfate is much more soluble that sodium sulfate, anyway it is difficult to predict solubilites on non-water solutes (concentrated sulfuric acid has no free water, only hydrates of sulfuric acid)

But you could of course distill nitric acid
with nitrates and sulfuric acid :)

osamafon - 23-3-2003 at 23:20

the patent says something like that petn can be made so 100g. PE to 500g. hno3 then a little petn forms if u add 500g. h2so4 more petn forms but its not so dangerous if u add pe to h2so4 and this mix to hno3. h2s207 is something like oleum it makes more +NO2 OH-with hno3, with water H2S2O7+H2O=2H2SO4 does it not carbonises if I add pe to mix. I once mixed H2SO4 and NH4NO3 when I add a drop of H2S04 formed 40-200ml brown NO2-NOx I never dried alkaliNO3. if alkali nitrates do not smoke- if I`m right is that so 2H30+ (-2)SO4