chornedsnorkack
National Hazard
Posts: 522
Registered: 16-2-2012
Member Is Offline
Mood: No Mood
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Alkali metal/peroxide sensitivity?
Alkali metals spontaneously form peroxides and hyperoxides on contact with air.
These are oxidants, and remaining metal should be a good reducer.
And the oxidants should also readily mix with the reducer.
For example, eutectic NaK has density of 866 g/l at 20 degrees.
All Na and K peroxides and hyperoxides are much denser:
KO2 - 2140 g/l
Na2O2 - 2805 g/l
Does NaK metal readily and quietly reduce the peroxides and hyperoxides on contact?
Oxides are also dense:
Na2O - 2270 g/l
K2O - 2320 g/l
So, potassium hyperoxide would form at NaK surface because that´s where air is. At which size would the KO2 grains overcome the surface
tension of NaK liquid by their weight, and sink to bottom? Once they do, would they quietly absorb extra K turning into inert K2O
throughout, or would a thin surface layer of K2O preserve the KO2 inside?
If the precipitate of KO2 soaked with NaK between the grains were disturbed, could the reaction
KO2+3K->2K2O
go to completion suddenly and exothermally?
How sensitive is KO2/NaK mixture to being set off? Does it just deflagrate, or is it able to detonate?
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PHILOU Zrealone
International Hazard
Posts: 2893
Registered: 20-5-2002
Location: Brussel
Member Is Offline
Mood: Bis-diazo-dinitro-hydroquinonic
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When cutting through the peroxide or superoxide crust ... naked metal underneath comes into direct contact with it and it explodes fiercely...this a
known danger of handling old air oxidised alkali metals...
The reaction can't be a detonation because the ingredients are not correctly mixed (read inhomogeneous)...any trial to make it homogeneous will simply
result into a fire or explosion.
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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