Fyndium
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Caution when bottling aerosol contents
I extracted some solvent from aerosol packages due to them being cheap and easily available in needed quantity by emptying them in a flask fitted with
condenser. The fluid cools down to cryogenic so evaporation is negligible, but this has another issue.
The fluid may absorb the propellant, which is usually butane/propane. I let it stand for a while to warm up and then bottled it. I checked the bottle
sometime later for some reason and vented it just in case, and it had built a huge pressure inside, it was like releasing a gas tank valve. The liquid
boiled when swirled, so I let it stand overnight with the cap loose just in case. The next day it did not build up any pressure anymore after any
manipulation or time.
Luckily the bottle was of thick glass GL45 reagent bottle so it withstood the unknown pressure, but if it would have blasted, it would have been a
major hazard.
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unionised
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I once did that with some "spray foam".
For reasons that don't really matter here, I was asked to analyse a few tins of it.
I started by slowly emptying a can into a large RBF with some DCM in it.
Seemed to work OK. Most of the propellant vented off and the contents dissolved in the solvent.
Then I left it to warm up.
And, when I picked it up the stuff formed like crazy + made a huge mess.
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Fyndium
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I suggest refluxing the extracted fluid in order to drive off majority of the butane/propane. It seems that some will carry over even so long as
through distillation, as I redistilled some recovered solvent and upon heating it started bubbling from 40C+ and gas trap emitted a lot of bubbles.
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Sulaiman
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You were probably lucky that the propellant was butane
because most glass bottles (and their caps) can withstand the vapour pressure of butane
(1 bar @0C, 2 bar @25C...)
If it was propane the pressure would be about 5x higher
which would be MUCH more dangerous.
CAUTION : Hobby Chemist, not Professional or even Amateur
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Fyndium
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MSDS lists 10-20% of butane and 5-10% of propane, so there certainly was some, but likely most of it evaporated during emptying the aerosol as propane
boils off much more faster than butane. But indeed, it was better to learn it the easy way, a thick walled glass bottle can only withstand more
pressure so that when it goes off, the boom is much bigger. And it was 2L bottle, so prepare for a big bang. The caps, btw, likely withstand pressures
even as high as 10bar, the glass vessels give up before. I remember a guy testing soda bottles with pressurized air and they bursted between 6-10bar.
This is to say, afaik safety factor for 10bar gas cylinder is 5x, so the burst pressure is 50bar so a safe working pressure for soda bottle would be
1-2bar max.
I extracted some more just recently, and it seems that refluxing it for a while and distilling it will remove most of the dissolved gases for good.
Caution must be done venting them, and I just put the exhaust tube into air duct that vents air directly outdoors. I used a CaCl2 bath cooled to -30C
with 3n rbf immersed, with valve takeoff adapter, reflux column and a thermoprobe to drain the aerosol bottles, and the reflux column was cooled with
cold water and was vented directly to exhaust. When drained, I removed the bath and replaced it with steam bath and slowly heated the flask to the
solvent BP and kept it there for a while. Then transferred it to a still and fractional distilled the solvent. I monitored the bottle for the evening
and no hiss was noted when loosening the cap, and overnight no pressure buildup was noted so I consider it safe.
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unionised
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If the propellant had been propane, much more of it would have left the solution before bottling.
I really don't know which would lead to a higher pressure in the bottle.
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Fyndium
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I bottled it somewhat cold, so when it warmed to room temp, the presumed butane would likely have been the cause. Likely an user error, as usual. Bad
chemists blame chemicals.
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