Maddr33
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Purify the benzoic acid from a mixture with benzyl alcohol.
I would love to show crystallization.
Solvents: acetone, ethanol, methanol, ethyl acetate, hexanes, dichloromethane
Aqueous solutions: 1M NaOH, 1M HCl, 3M NaOH, 3M HCl, 1 M NaHCO3, saturated NaCl
Drying Agent: sodium sulfate
I wish there were a sim lab where I could mix these things and practice extraction.
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madscientist
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Thread Moved
15-3-2015 at 02:18 |
Boffis
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Neutralise the acid with dilute NaOH and steam distil or extract with immiscible solvent, of those listed probably hexane is best and fractionate the
extract. You don't need much solvent because benzyl alcohol is pretty insoluble in aqueous salt solutions anyway. If you have produced this mixture by
Cannizzaro's reaction from benzaldehyde you should get phase separation anyway. Check out Vogel's Textbook of organic chem.
The free acid can be recovered with dilute HCl on the aqueous phase.
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Maddr33
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thanks you...
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sparkgap
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Sodium hydroxide will work, but even a bicarbonate solution will do the job for extraction, after which you do the requisite acidification and salting
out to net your benzoic acid.
sparky (~_~)
"What's UTFSE? I keep hearing about it, but I can't be arsed to search for the answer..."
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