weiming1998
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The effect of glycerol on calcium hypochlorite
I once tried glycerol with calcium hypochlorite at high temperatures. Needless to say, it bursted into flames. Today, though, I was trying to wrap
calcium hypochlorite and glycerol together in aluminum foil, when the mix started fizzing.
The mix fizzed, and then made lots of smoke, then the whole mixture went on fire with a bang. Or more like a pop. blasting the aluminum foil to bits.
The reaction was quite a bit more violent than potassium permanganate+glycerol, but it might just be the size of the samples. I only dipped a few
drops on quite a large pile of hypochlorite (compared to the drops), though.
Now, on the exaggerated MSDS though, glycerol has a surprising reactivity of 0! (http://www.sciencelab.com/msds.php?msdsId=9927350)
I wouldn't class something that spontaneously catches fire/explodes when it touches oxidizers as a reactivity of 0!
Any thoughts?
Note: It was glycerol (C3H8O3) not propylene glycerol (C2H7O2), so I don't think it had been talked about on the forum. Also, I don't think that the
reaction, nor the materials, were energetic enough to be posted in the energetic materials section.
[Edited on 22-1-2012 by weiming1998]
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Adas
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Ca(ClO)2 is very reactive oxidizer - it self-ignites on contact with higher alcohols or sulfur. No surprise for me it catched fire.
It probably converted the glycerine into glyceraldehyde? And then the reaction temp. rised so fast, that it started burning.
Rest In Pieces!
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weiming1998
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Ca(ClO)2 doesn't burst into flames on contact with sulfur like glycerol does, but sometimes emits a nasty-smelling gas. (very likely chlorine) Also,
very flammable primary alcohols does nothing to Ca(ClO)2, except when it's burning, which in this case ignites the whole pile with a flash of orange
light and a sound like a gun going off. It doesn't emit much smoke though, like glycerol, which a few drops on hypochlorite can cloak my backyard in
foul smelling opaque smoke that smells a bit like burning plastic. Also, calcium hypochlorite auto-emits oxygen at high temperatures (sometimes even
the temperature of boiling water can get hot enough for the Ca(ClO)2 to emit oxygen in large bubbles.)
Also, I don't think it is glyceraldehyde because:
1, It probably will decompose at those temperatures
2, Glyceradlehyde is produced by the "mild" oxidation of glycerol. (Wikipedia http://en.wikipedia.org/wiki/Glyceraldehyde). I don't think smokes, bangs, flames and high temperatures are mild oxidation.
But why is the reactivity of glycerol 0? The MSDS have a reputation for making chemicals sound more dangerous than it really is. So the expected
reactivity score for a MSDS would be 2-3. Even a sane reactivity score would be 1 or 2, but 0?
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Adas
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Here is the video of S + Ca(ClO)2
http://www.youtube.com/watch?v=dENDpGR_OAk
Rest In Pieces!
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weiming1998
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They grinded it into a very fine powder. I just used the granules. Maybe mine wasn't fine enough? Or maybe I didn't stir it much?
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Poppy
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Potassium chlorate, which I thought is supposed to be more reactive than calcium hypochlorite, does not self ignites when mixed with sulphur even if
you scratch hard the mixture against motar and pestle. The mixture only detonates when hit wth a hammer.
Thnaks on providing information on how cruel calcium hypochlorite is. Maybe thats something relates to calcium hydroxide/ carbonate/ sulfide/ sulphate
solubility which makes the hypochlorite part of the molecule to be released much easier?
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weiming1998
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Calcium hypochlorite releases its oxygen atom very easily, at barely 100 degrees. Even a very strong oxidizer like potassium chlorate only releases
oxygen at a temperature of 350 degrees Celsius, Potassium permanganate does that at 220 degrees Celsius. So naturally, it is more able to
spontaneously combust by friction. and once oxygen is released, it's an unstoppable chain reaction that ends up with a big bang and smoke. Also,
calcium hypochlorite slowly decomposes in water to Ca(OH)2 and HClO. Is hypochlorous acid a weaker acid than H2O?
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