TheNerdyFarmer
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Drying Ethanol
I recently purchased 250ml of ~96 percent undentured ethanol. I planned on drying it with initially with magnesium metal. But I also have <400 g of
color changing silica gel. Would silica gel work in the drying ethanol? If not, why not. Thanks in advance.
I ask this because silica gel is cheap and insoluble in ethanol.
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macckone
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You probably want another drying agent before the silica gel.
Silica gel is actually a good drying agent but it doesn't remove
a lot of water per gram. Potassium carbonate will cause 96%
ethanol to separate for use in a separatory funnel. Potassium
hydroxide is also a good drying agent. As is calcium oxide,
but high grade can be hard to obtain.
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NEMO-Chemistry
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I havnt tried it myself but would magnesium sulphate work to get the bulk out? Personally i would use a salt method first before trying sodium metal.
From my reading it seems sodium is best used for water content 1% and below.
Be aware Ethanol sucks water quicker than sodium hydroxide in air!! one of those jobs for a bone dry low humidity day  .
I am sure you are aware but dont try and dry with conc sulphuric acid, you dont get what you think your going to get , yes it was my first attempt at drying lol
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NEMO-Chemistry
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Quote: Originally posted by NEMO-Chemistry  | I havnt tried it myself but would magnesium sulphate work to get the bulk out? Personally i would use a salt method first before trying sodium metal.
From my reading it seems sodium is best used for water content 1% and below.
Be aware Ethanol sucks water quicker than sodium hydroxide in air!! one of those jobs for a bone dry low humidity day .
I am sure you are aware but dont try and dry with conc sulphuric acid, you dont get what you think your going to get , yes it was my first attempt at drying lol |
Dont you get ether adding conc Sulphuric acid? I ask because i was going to give it a try
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Loptr
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| Quote: Originally posted by NEMO-Chemistry | | Quote: Originally posted by NEMO-Chemistry | I havnt tried it myself but would magnesium sulphate work to get the bulk out? Personally i would use a salt method first before trying sodium metal.
From my reading it seems sodium is best used for water content 1% and below.
Be aware Ethanol sucks water quicker than sodium hydroxide in air!! one of those jobs for a bone dry low humidity day .
I am sure you are aware but dont try and dry with conc sulphuric acid, you dont get what you think your going to get , yes it was my first attempt at drying lol |
Dont you get ether adding conc Sulphuric acid? I ask because i was going to give it a try |
Diethyl ether formation occurs at a temperature of 130-140*C. You would probably see Le Chatelier's principle at work if you just stored ethanol with
sulfuric acid with suppressed formation because you wouldn't be removing the ether as it formed. I am not sure what the other side products would be,
or if ethyl sulfate or diethyl sulfate would be formed under these conditions, and if it did it would still be in equilibrium.
[Edited on 10-7-2017 by Loptr]
"Question everything generally thought to be obvious." - Dieter Rams
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NEMO-Chemistry
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| Quote: Originally posted by Loptr | | Quote: Originally posted by NEMO-Chemistry | | Quote: Originally posted by NEMO-Chemistry | I havnt tried it myself but would magnesium sulphate work to get the bulk out? Personally i would use a salt method first before trying sodium metal.
From my reading it seems sodium is best used for water content 1% and below.
Be aware Ethanol sucks water quicker than sodium hydroxide in air!! one of those jobs for a bone dry low humidity day .
I am sure you are aware but dont try and dry with conc sulphuric acid, you dont get what you think your going to get , yes it was my first attempt at drying lol |
Dont you get ether adding conc Sulphuric acid? I ask because i was going to give it a try |
Diethyl ether formation occurs at a temperature of 130-140*C. You would probably see Le Chatelier's principle at work if you just stored ethanol with
sulfuric acid with suppressed formation because you wouldn't be removing the ether as it formed. I am not sure what the other side products would be,
or if ethyl sulfate or diethyl sulfate would be formed under these conditions, and if it did it would still be in equilibrium.
[Edited on 10-7-2017 by Loptr] |
thanks, its something I would like to try at some point
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nezza
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You can't dry ethanol with sodium. It reacts to form sodium ethoxide and hydrogen. The problem with drying it with sulphuric acid is that the two are
miscible in all proportions so you get a mixture which you cannot distil without some ether formation. Again Alkali hydroxides are soluble in ethanol
so it would need to be distilled off. Calcium oxide is supposed to be a good drying agent and some books say metallic Calcium can be used ti dry it. I
have always found that Calcium reacts slowly with ethanol though.
If you're not part of the solution, you're part of the precipitate.
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