sonogashira
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Using sodium hydrogen sulfate as a "dry acid"?
I had a thought about using sodium hydrogen sulfate (sodium bisulfate) to mix with NaCl, NaOAc etc. and dry-distill to get anhydrous HCl, HOAc etc.
I can't try it out at present since I haven't got any sodium bisulfate so I wondered if anyone else had done any similar experiments?
If not I might get some next week and do some test-tube experiments
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smuv
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Sodium bisulfate is usually sold as the monohydrate and IIRC it is hard to dehydrate without forming the pyrosulfate. Also, in my experience dry
distillations are not as convenient as they may seem on paper.
I did some experiments a while ago with sodium bisulfate monohydrate and sodium chloride. I ground the two together with a mortar and pestle and to
my surprise a faint smell of HCl was noted on grinding the two to make an intimate mixture. I put everything in a flask and heated it over open
flame; the HCl production was really slow, and useless to make large quantities of HCl.
For preparative purposes I would just use sulfuric acid to make your HCl and just buy glacial acetic acid commercially. Of course there is nothing
wrong with experimentation though.
PS You might get unexpected results with sodium acetate, pyrolysis might occur under your reaction conditions to produce methane.
"Titanium tetrachloride…You sly temptress." --Walter Bishop
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kclo4
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My my, is Sodium Bisulfate the chemical of the week or what?
I think NaHSO4 works best as an acid in a concentrated solution from my experience. I used it a lot before I acquired Sulfuric acid. I thought it was
pretty cool stuff at the time, but I don't remember ever being impressed by its acidity when molten or as a powder.
It also dissolves in Ethanol to precipitate Sodium Sulfate. I believe it does anyways, I have never done it but I have read that many times. This
might be of some interest for those who cannot obtain H2SO4, because then it would allow for reactions to happen with out much heating but you'd
essentially be using a sulfuric acid-ethanol mixture. That mixture might be good for producing things like HCl, if its your last option. Other acids
wouldn't be good though, like Acetic acid for example might form some Ethyl Acetate.
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Panache
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Quote: | Originally posted by kclo4
It also dissolves in Ethanol to precipitate Sodium Sulfate. I believe it does anyways, I have never done it but I have read that many times. This
might be of some interest for those who cannot obtain H2SO4, because then it would allow for reactions to happen with out much heating but you'd
essentially be using a sulfuric acid-ethanol mixture. That mixture might be good for producing things like HCl, if its your last option. Other acids
wouldn't be good though, like Acetic acid for example might form some Ethyl Acetate. |
This is interesting if its appreciably true because you would then have a solution thats on its way to producing di ethyl ether, or sodium ethyl
sulphate, both useful and annoying to make. However i'm sure my grandfather did some thinking along these lines also, perhaps following on from work
started by his father.
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kclo4
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True! I found the quote below on this thread: http://www.sciencemadness.org/talk/viewthread.php?tid=2995&a...
Quote: |
Originally posted by Boomer
....But now that problem has been fixed. Sodium ethyl sulfate can be easily prepared in the home laboratory from common sodium bisulfate found in pool
pH down and 95% pure grain alcohol, and baking soda or sodium carbonate found in pH up.
113 parts by weight of sodium bisulfate and 20 parts by weight of pure grain alcohol are combined in a flask and brought to boiling upon which time
the sodium bisulfate crystals disappear and sodium sulfate forms.
When the reaction has been completed, the flask was is immersed in an ice bath and vigorously stirred until the tempurature rapidly goes below 32.3C.
The formed sodium sulfate is thus filtered out leaving an anhydrous ethyl hydrogen sulfate/ethanol mix.
The excess ethanol is distilled off, and the ethyl hydrogen sulfate is neutralized with an appropriate quantity of sodium carbonate leaving sodium
ethyl sulfate.
Simple... thats all there is to it! The secret to how it works is the excess sodium bisulfate when rapidly cooled below 32.3C forms the decahydrate,
or Glaubers salt, and this sucks the water out of the reaction.
This is discussed futher in US Patent number 3,024,263. |
I haven't read much into that thread so I don't know if it is determined false, etc, but It seems like it can form H2SO4 in ethanol, which then could
be used to produce dry acids.
[Edited on 25-10-2008 by kclo4]
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