tryptic
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Dichloromethane from paint remover
Is it possible to distill DCM from ordinary paint remover..? I read that paint removers contain some stuff that make it evaporate less easily, is this
a problem..? If the paint remover contains some methanol, will some of this still be present in the distilled DCM, are two or more distilling rounds
necessary for reasonably pure DCM?
Any major health risks involved with distilling DCM, assuming that you do it outside or with good ventilation..?
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Haggis
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I've recently attempted methods of extracting the DCM that doesn't involve distillation. My paint remover is "Zip-Strip" brand,
and is proving a hassle.
My first thought was perhaps the goo was soluble in water, so I stirred a bit in a flask of water and nothing happened. My second train of thought
brought me to the conclusion of making an emulsion. I added some Zip-Strip to the flask, along with some water. I also absentmindedly added a
rubber stopper on top of this all. I shook it vigorously until I heard the stopper impact the ceiling, and I was sprayed with DCM.
This effectively made an emusion, and the goo was hanging limply in the bottom of the flask. During one test, I poured this through filter paper.
This took entirely too long, and I recovered only a small amount of DCM. Thinking that pouring this through a filter paper takes too long, I poured it
through a fine screen. It went much quicker, and a much larger portion of DCM was resting on the bottom, with a small amount of goo that presumably
didn't get 'tangled' in the filter resting on top of it.
This method isn't the best, as it is quite long and bothersome. This could be done, however, for those on a budget to extract crude DCM from
their paint strippers. I am now heading for distillation.
Great ideas often receive violent opposition from mediocre minds.
<b> <a href=\"http://pgp.mit.edu:11371/pks/lookup?op=get&search=0xEE41A2B1\">PGP Key</a> </b> 0C0A 7486 B97F
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tryptic
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Yeah..BTW, if I buy a random brand of paint remover from a hardware store, is there any chance that it is an azeotropic mixture..? From a product
viewpoint it could make sense if it makes the paint remover evaporate less easily, but for extracting DCM it'd of course be a real pain..
Does DCM form azeotropic mixtures with methanol for example..?
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tryptic
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According to this article, a mixture of 93% DCM, 7% methanol seems to be azeotropic at least..:
http://www.rsc.org/CFCart/displayarticleeonfree.cfm?article=8-9%223%24_F%2BB!4._L%3D(6%2CG%5B4-T7PE%2C%3D29%23%3C%0A
Maybe the azeotropicity goes away with lower concentrations of DCM..Would mean that it makes sense to buy paint remover with _less_ DCM. I guess the
Merck index or some similar book would have more data on this..
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