norm
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acetylene
Quite a time ago I bought and oxy-acetylene kit from a store which has since closed down, ugh! They told me to have the cylinders charged with gas at
a gas depot. This I did some time ago and the oxy one came back filled OK but the acet. one they said it would be too unstable to fill her up cos
there was somethin' missin'.
My question is what is missing and can I do somethin' to get it back to normal?
Thanks guys.
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stygian
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I think acetone and pumice (could be wrong about the pumice) are used to stabilize acetylene under high pressure.
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pyrochem
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The acetylene is dissolved in acetone, but it might be hard to refill the tank. Best bet would be to get a new tank.
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Madandcrazy
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Is acetylene gas not expedient when acethaldehyde should be prepared, gas is passed with water steam over a hot catalyst in a destilation equipment.
I think easy chemicals are useful too with the tripple binding between the two carbon atoms, maybe 2-hexyne or diphenylacetylene.
Pyrochem you mean the easy  synteses of glykuril ?
Can it synthesized by urea and acetylene gas when urea is dissolved in a solvent and
acetylene gas is bubbled through the mixture ?
Perhaps a method is when urea is treated with tetrachloroethane [tetrachloroethylene ] in a selected solvent.
Interested to this maybe how prepared n,n`-malonylurea in a additional process, by n,n-dimethylurea, acetylacetone ... ?
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Mr. Wizard
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Acetylene is unstable as a pressurized gas, at anything over 15 psi. The trick they use is to dissolve the gas in acetone, which is carried in a
sponge made of pumice, asbestos or some kind of lightweight concrete. There may be other materials used for the sponge. Think of it as your would CO2
dissolved in soda water. If the acetylene bottle is used while horizontal, sometimes the acetone will leak out. I've never had a gas cylinder company
tell me a bottle was bad, unless it's some sort of mechanical problem with the valve, threads, or physical tank damage. They are also very picky about
tanks having protective caps on them to protect the valves when dropped, and about having test dates stamped on them. The company filling the tank
should make sure it has the right amount of acetone in it. I would be reluctant to add acetone to a tank, not knowing what the amount should be. Maybe
the tank has been dropped and the pumice sponge has been damaged. If they won't fill it you are left with few choices but replacement. If they are
the only source of the gas, you have no options, but to buy a new tank. 
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unionised
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I see Madandcrazy has set a new record for being totally off topic.
As Mr waiiard points out, since they won't refill your tank you need a new one. It might be that the acetone has evaporated or been spilled. It might
be that they can read date codes and think your tank is too old. They may think that the pumice (or whatever) is past its best. It doesn't make any
difference why they won't fill it. The fact is that they won't
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Madandcrazy
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I don`t understand your reply.
I mean only someting to possibilityes to a cycloaddition, possiply to the n,n`-malonylurea.
Can it prepared by chlorinated (brominated) acetyacetone and urea or better by oxidation ?
CH3C=OCH2CO=CH3
-->
CHCl2C=OCHClC=OCHCl2 ?
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unionised
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I should probably know better than to reply but here goes.
What I mean is that your posting has got absolutely nothing to do with acetylene and that, since the topic of this thread is acetylene, your posting
is nothing to do with the thread. Postings that have nothing to do with the thread are off topic.
So, I ignored your post and replied to the actual thread (and I messed up typing "Mr Wizard").
I can't help wondering if you have been testing some substituted malonylureas personally.
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