bluamine
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How to separate acetic acid from aceton?
Hi everyone!!
I'll do a wood pyrolysis process and I want to condense the vapours into liquid form. As I read in my french vintage high school book, it's about a
mixture of water, acetic acid, and acetone?
So guys, Do they form any form of azeotropes there? Or I just have to use the difference in boiling/freezing points to separate them from each other.
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Texium
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Unfortunately, wood pyrolysis is much more complex than your textbook would make it sound. Methanol is also a major pyrolysis product, and there could
be other volatile products too depending on the type of wood being used. Additionally, wood pyrolysis will always produce significant amounts of
various phenols and furans, some of which may be carried over with the more volatile substances.
If you end up doing this, don’t expect to condense anything resembling a pure compound out of the initial pyrolysis. You’ll have to collect a
crude distillate, and then refine it from there. It would be easiest to remove acetic acid and other possible carboxylic acids by simply treating the
distillate with sodium bicarbonate. Then you could try distilling the mixture more gently to separate the most volatile compounds (methanol, acetone)
from the higher boiling crud. Further purification of this would be difficult without a really efficient fractionating column, but at this point you
could dry the distillate and be left with a sort of crude “wood alcohol” that would make a good cleaning solvent if nothing else.
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Texium
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Thread Moved
9-4-2022 at 09:18 |
bluamine
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Quote: Originally posted by Texium  | Unfortunately, wood pyrolysis is much more complex than your textbook would make it sound. Methanol is also a major pyrolysis product, and there could
be other volatile products too depending on the type of wood being used. Additionally, wood pyrolysis will always produce significant amounts of
various phenols and furans, some of which may be carried over with the more volatile substances.
If you end up doing this, don’t expect to condense anything resembling a pure compound out of the initial pyrolysis. You’ll have to collect a
crude distillate, and then refine it from there. It would be easiest to remove acetic acid and other possible carboxylic acids by simply treating the
distillate with sodium bicarbonate. Then you could try distilling the mixture more gently to separate the most volatile compounds (methanol, acetone)
from the higher boiling crud. Further purification of this would be difficult without a really efficient fractionating column, but at this point you
could dry the distillate and be left with a sort of crude “wood alcohol” that would make a good cleaning solvent if nothing else.
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Oh yes methanol is also mentioned in other books IDK how didn't they mentioned it in that textbook!!
I was thinking about neutralising acid method but I think I must read more about it
Thanks anyway
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