Extraction of caffeine from tea, coffee, cola, and cocoa has been done thousands of times in ungraduate experiments.

This year, I asked the students to extract caffeine from a source of their choice the week after they performed the classic "tea-riffic" experiment.

That generated a nice buzz. I discovered that orange soda has caffeine in it!

08_caffeine1.pdf

08_caffeine2.pdf

Formation of emulsions and obtaining enough caffeine to see seem to be the main problems encountered.

In my experience a 250 mL separatory funnel is helpful to do the experiment on a scale where students obtain enough caffeine to see.

In my folder, I have emulsion-busting strategies - what to do when students shake the tea too hard.

Its rather wasteful of dichloromethane.

I use DCM instead of ethyl acetate because its easier to keep the aqueous layer in the separatory funnel.

I do not recommend using milk based products, reason why is that upon adding the base, the milk will curd. The solid curd will need to be filtered out. and the problem is that there is alot of solid, so removing it will take time since the Buchner filter will clog up after so much solid has been collected. I believe it took me three Buchner filtrations to completely separate the liquid from the solid.

-Ricardo Rodriguez

 Create your own educational wiki!HelpPublic, Silver wiki Privacy Policy RSS