DFliyerz
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Replacing Sulfuric Acid with Sodium Bisulfate
I know that in a fair number of reactions concentrated sulfuric acid can be replaced with solid sodium bisulfate due to it's low melting point, such
as making nitric acid from nitrates and glacial acetic acid from sodium acetate, but can it be used in reactions such as esterification of carboxylic
acids? What else can it be used in?
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blogfast25
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Quote: Originally posted by DFliyerz  | | [...] but can it be used in reactions such as esterification of carboxylic acids? What else can it be used in? |
I doubt very much if bisulphate has enough protonating power to protonate carboxylic acids, as required by the Fisher esterification mechanism.
Bisulphates will also not be soluble in or miscible with carboxylic acids which would lead to heterogeneous catalysis.
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brubei
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any other mineral acid work too, paratoluenesulfonic acid (APTS) is also a common organic acid suitable for esterification
[Edited on 3-4-2015 by brubei]
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blogfast25
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| Quote: Originally posted by brubei | any other mineral acid work too, paratoluenesulfonic acid (APTS) is also a common organic acid suitable for esterification
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Something tells me that someone clearly looking to replace sulphuric acid by a bisulphate won't have access to paratoluenesulfonic acid. 
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papaya
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Is it true that heating bisulphate yields sulfuric acid that can be distilled and collected, or was it only SO3 ?
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DFliyerz
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Also, it can be used to make hydrochloric acid from sodium chloride. So from what I can see, it's kinda like a sulfuric acid solid.
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blogfast25
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| Quote: Originally posted by papaya | | Is it true that heating bisulphate yields sulfuric acid that can be distilled and collected, or was it only SO3 ? |
First it decomposes to sodium pyrosulphate, which around 500 C starts releasing SO<sub>3</sub>.
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DFliyerz
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Apparently though it doesn't need to decompose to make glacial acetic, and it's actually bad for it to decompose for that synthesis: https://www.youtube.com/watch?v=QQWvgLxtldc
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blogfast25
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Well no. To displace acetic acid from sodium acetate with a stronger acid you basically need about 120 C, just above the BP of acetic acid.
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