Mixe
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Alternative to DCM?
Noob question, but is there an alternative to dichlormethane that works identically as a solvent? The substance is illegal in my country.
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DraconicAcid
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Nothing's ever identical, but dichloroethane is very similar, apart from a significantly higher boiling point.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Sulaiman
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No
only identical molecules will behave identically,
what is it that you wish to use DCM as a solvent for ?
maybe a suitable substitute is available.
CAUTION : Hobby Chemist, not Professional or even Amateur
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Mixe
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I intend to use it as a solvent for extracting various substances from pills and capsules. I don't know exactly which substances yet, but I need it as
part of the water/ethanol/acetone/dichlormethane battery for performing fractional extractions.
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byko3y
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Obvious candidates are chloroform and dibromomethane.
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DraconicAcid
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Ethyl acetate might work.
ETA: Chloroform, yes (although if dichloromethane is illegal, he may have trouble getting chloroform). Dibromomethane is not going to be a great
choice because organic bromides are more reactive and more expensive than organic chlorides.
[Edited on 13-6-2017 by DraconicAcid]
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Melgar
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I doubt there's a single person on these boards that actually buys chloroform as such, other than maybe professional chemists. That doesn't mean it's
unattainable. It's probably the most accessible of all the halogenated solvents. Of course, if DCM is illegal in OP's country, it's probably because
people like him use it to do exactly what he's doing, so I'm a bit hesitant to offer more advice.
The first step in the process of learning something is admitting that you don't know it already.
I'm givin' the spam shields max power at full warp, but they just dinna have the power! We're gonna have to evacuate to new forum software!
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clearly_not_atara
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Indeed the synthesis of chloroform from acetone or ethanol with hypochlorites is a common first reaction for budding amateur chemists.
1,2-dichloroethane isn't much harder if ethylene glycol is available.
Ethyl acetate is a little more work as you have to get relatively dry acetic acid. I think ethyl formate can be made relatively easily by the
Tischenko reaction with formaldehyde/ethoxide; it has some favorable properties like a low boiling point, moderate polarity, and it's a bit less
flammable than ethers.
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JJay
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Diethyl ether is not exactly identical, but like DCM, it is easy to evaporate. It is much more flammable than DCM.
I don't really see a problem helping the OP find a legal way to get around his local laws. That stated, I hadn't realized that DCM is restricted
anywhere.
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Corrosive Joeseph
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Ethyl acetate is available as 'acetone-free nail varnish remover'...........
Dichloroethane from antifreeze, zinc and HCl -
"Reflux ethylene glycol in an excess of zinc chloride and conc. hydrochloric acid,
distill out the low boiling 1,2 Dichloroethane from the reaction mixture"
https://www.sciencemadness.org/whisper/viewthread.php?tid=72...
DCE can also be animated in the classic 'pipe bomb' to ethylenediamine "under pressure at 180c in aqueous solution"
https://en.wikipedia.org/wiki/Ethylenediamine
/CJ
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clearly_not_atara
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To clarify, most nail polish removers contain a mixture of solvents. Sometimes you'll get lucky and it's pure acetonitrile, but usually you have a
mixture of ethyl acetate, butyl acetate, ethyl lactate, diethyl glutarate/succinate/adipate and some fragrances. This is to lower the volatility while
retaining the good solvent properties of light esters.
But the real message is just to read ingredient labels on interesting little off-brand products. One day you'll find 2% triflic acid being sold as a
toilet bowl cleaner or something.
[Edited on 14-6-2017 by clearly_not_atara]
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adk
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I haven't heard of DCM being illegal in any country. Even here in Australia, a country with some of the tightest legislation relating to chemicals, it
is readily available from all chemical suppliers, automotive vendors (paint strippers) and cheap. Many laboratories and chemists in general prefer to
use other solvents (ethyl acetate, for example) because they are not as toxic and do not require special [i.e. expensive] waste disposal. Also, ethyl
acetate tends not to form emulsions when used for liquid/liquid extraction. It also does not eat everything (e.g. paint on your lab stands or rotary
evaporator).
1,2-dichloroethane (ethylene dichloride, EDC,DCE) is one alternative but it is flammable and significantly more toxic than DCM. It has a higher
boiling point (~83C vs ~40C), similar solvating properties but has a relatively low heat of vapourisation so it is still easy to distill. It is
extensively used in the production of vinyl chloride monomer and on an industrial scale, is likely easier to obtain.
You could use chloroform which some of the benefits of DCM but a higher boiling point and heat of vapourisation - meaning it's probably safer. Easy to
synthesise in small quantities from acetone and Chlorine bleach via the haloform reaction (check youtube or the search engine on here for
instructions). Larger reactions will be harder to control and if you need more than a few hundred mL it's probably a frustrating and expensive way of
obtaining chloroform.
My recommendation is to look for an alternative, especially if you're not using it in a lab with fume extraction equipment. Chlorinated/halogenated
solvents are pretty bad for your health and the environment. Not to mention, the possibility of being illegal - definitely avoid undertaking illegal
activities for obvious reasons.
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Mixe
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DCM is practically illegal in all of EU, according to EU regulation 1907/2006, except for certified professionals. It has nothing to do with illegal
extraction of narcotics, but everything to do with its long-term enviromental impact. In my country it's totally prohibited for non-professionals to
buy, handle or store. It's still used in some EU countries, but I can't legally import it.
And actually, I'm really not planning on doing something extremely illegal with it. I was planning to extract PABA from PABA capsules for subsequent
synthesis of benzocain, which may be regulated and possibly slightly illegal, but not dramatically so.
And since I bought a soxhler apparatus I thought I'd stock up on chemicals for separations. That's all.
I guess I'll try with ethyl acetate then. It's just that the solubility of the different compounds are often given in water, alcohol and DCM. I'm not
sure how translatable it is to ethyl acetate.
[Edited on 2017-6-14 by Mixe]
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alking
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Ethyl acetate is likely more comparable to DCM than Ethanol, but it will fall somewhere between those two on the polarity spectrum. Depending what you
are doing ethyl acetate may work just fine, on a straight extraction as you mentioned it probably will.
You may want to get something less polar as well such as a straight chain alkane (hexane, heptane, etc), that will allow you to do an even more
selective extraction. You want to go from the least polar to the most when doing an extraction/separation of various compounds. With ethyl acetate the
biggest drawback in using it as a nonpolar is that it hydrolyzes to EtOH and AcOH in acidic or basic conditions which means you can't use it for an
a/b extraction which is likely something you will want to do depending the extent you're intending to process the various compounds.
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