Jor
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Registered: 21-11-2007
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ethanol, MEK or MeOH
What would you guys recommend to buy. I am about to buy a liter of ethanol, but I dont want to buy the very expensive duty taxed stuff. So I have the
choice of buying it with 5% by weight of MeOH or 2% MEK. I currently have about 400mLs left of EtOH containing 1% MEK, however i only used it for
washing inorganic salts and doing some recrystallisations.
Can the MEK be easily removed if I am ever going to perform a reaction where this really interferes? Such as when you prepare a sodium ethoxide
solution you would get condensation products right? Would adding half (or more) the volume of aqueous bisulfite solution followed by filtration and
distillation give pure 96% EtOH?
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Sedit
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I would go with the MEK tainted stuff since it would be simpler to remove if you really need to. Is there H2O in this Ethanol Jor?
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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Jor
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No it's about absolute ethanol from Acros. The problem is that Carl Roth selled a liter aboslute with 1% MEK for only 8 euro, but it seems they have
withdrawn that product. 
So now I have to find an alternative ethanol source.
That is exactly the problem. The MeOH can almost not be removed while the MEk probably can, and it's present in lower concentration, however it does
need to be purifed in some reactions as ketones can give those nasty Dies-Alder condensation products.
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Lambda-Eyde
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Quote: Originally posted by Jor  |
That is exactly the problem. The MeOH can almost not be removed while the MEk probably can, and it's present in lower concentration, however it does
need to be purifed in some reactions as ketones can give those nasty Dies-Alder condensation products. |
Surely you mean Aldol condensation, not Diels-Alder reaction? 
I'd go for the MEK any day. It's less poisonous as well as being easier to separate when needed.
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