quest
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synthesis for potassium benzoate
I found on frogfot site this synthesis for benzoic acid:
C6H5CH3 + 2KMnO4 ==> C6H5COOK + 2MnO2 + KOH + H2O
C6H5COOK(aq) + HCl(aq) ==> C6H5COOH(s) + KCl(aq)
Is there any way I can purify the potassium benzoate(C6H5COOK) that I got from mixing the Toluene and the Potassium permanganate?
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BromicAcid
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Filter the solution from equation #1
Extract the solution with several small slightly basified allocates of water.
Take water extracts and acidify, filter, wash with ice water, vacuum dry.
Pretty pure stuff from here, what purity are you looking for? 99.9999%?
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quest
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I want as pure potassium benzoat as I can....
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Polverone
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Filter the solution from the reaction, concentrate it as much as possible without anything crystalizing out, then acidify with HCl and collect the
slightly-soluble benzoic acid. Wash it with some cold water, then react it with pure potassium carbonate or hydroxide.
PGP Key and corresponding e-mail address
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