Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: lukas.stib on April 14, 2022, 01:54:49 PM
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Hello chemists,
please give me an advice. I want to make propionic acid by reacting sodium propionate with acid. I have 96% H2SO4, but I don't want to use it because I'm afraid it will destroy my propionate. It's already happened to me with sodium acetate, which turned black because H2SO4 dehydrated into elements. I don't know what acid would be effective. I have 85% phosphoric acid, can I use it? I want to get a lot of concentrated propionic acid, will the problem be 85% phosphoric acid?
Thank you. Lukáš S.
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Use diluted sulfuric acid 10 to 20 %.
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But it will be too much water ...
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Of course you have to do Destillation.
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And 85% phosphoric acid? I think this is better. Much less water and phosphoric acid also certainly reacts and has no destructive effects like H2SO4. Or 35% HCl is too good I think...
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You can do.
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Bear in mind propanoic acid forms a constant boiling point mixture with water. I note you want to make a lot of the concentrated acid so unless you particularly want to experiment with methods of further concentrating the azeotropic mixture it might be easier to just buy the concentrated acid.
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OK, thank you. I can't get propionic acid anywhere in the Czech Republic, so I wanted to try it from its sodium salt. I wanted it for esters, so maybe it would be more appropriate.
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One might be able to desalt a mixture containing sodium ions and an anion with a mixed-bed ion exchange resin. I am not sure how practical this is.
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And what about a mixture of propionic acid and water to dry some salt? Sodium sulfate?