How do you separate paracetamol and caffeine using high-school laboratory equipment?

I was thinking about using the fact that paracetamol has a lower melting point (169 °C) compared to caffeine (around 235 °C): I would heat them up till paracetamol melts while caffeine is still solid. What I can't figure out is how you filter the caffeine from the liquid paracetamol (filter paper would burn at such a high temperature).

I would like to know how you do the filtration at high temperature; or, if you have a better method, please let me know!

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    $\begingroup$ Caffeine is basic, paracetamol acidic. Any clues? $\endgroup$ – Waylander Sep 10 '17 at 12:47
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    $\begingroup$ @Waylander Would you like to elaborate on your idea as an answer? $\endgroup$ – Jingjie YANG Sep 10 '17 at 16:55

The answer that my teachers had in mind was column chromatography. Essentially we use the van der Waals force of silicon gel to do an elution of the caffeine / paracetamol solution dissolved in water.

More details can be found here: http://www.chemguide.co.uk/analysis/chromatography/column.html

  • $\begingroup$ I will mark this as accepted since there are no other answers. $\endgroup$ – Jingjie YANG Sep 14 '17 at 20:06

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