Chemgineer
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Acetic acid yellow/brown colour.
I've been dry distilling 100g sodium acetate with 175g sodium bisulfate and distilling off the acetic acid.
However when the reaction gets hotter the colour becomes yellow and even brown, i'm not sure what is happening.
Sodium sulfate melts at over 800 degrees so it shouldn't be an issue, sodium acetate doesn't melt until 300 degrees and I don't think i'm reaching
that temperature. And sodium bisulfate melts at 181 degrees but if anything I would expect this just to improve my yield of acetic acid.
Any suggestions on why the discoloration?
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j_sum1
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What is the source of your bisulfate? If it is pool grade, it can be pretty dirty.
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Tsjerk
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Bisulfate doesn't melt, it decomposes. I don't think the decomposition products will color your product, but anything organic could at those
temperatures.
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Chemgineer
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Yes the sodium bisulfate is from pool chemical supply.
I know anhydrous sodium bisulfate decomposes but this happens at around 315 degrees. I've just tested mine with a gas torch and mine definitely melts
and releases water so I think i've got monohydrate.
So I guess my original title of dry distillation is only partly right.
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Chemgineer
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Maybe there is also organic material in the sodium acetate if it has been produced from vinegar it could have sugar or barley residue included
perhaps?
I bought the sodium acetate from ebay as trihydrate and then heated it to anhydrous.
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