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Isolation of caffeine from tea

Need help with these 2 questions: ( isolation of caffeine from tea)

In this expermient caffeine is isolated from tea by extraction into water followed by extraction into dichloromethane, evaporation and sublimation.

1) why is lead acetate added to tea?

2) why is caffeine extracted 3 times with 20 ml of chloroform rather than once with 60 ml?

Any help would be great guys.
Reply 1
1) the lead acetate reacts with caffeine?

2) using anymore chloroform will not extract purer caffeine. Rather, recycling the unpure caffeine and extracting again will produce better results.
Reply 2
http://www.henriettesherbal.com/eclectic/bpc1911/coffea_caff.html

Lead acetate removes tannins and other colouring matter.
Google is great for those kind of questions.

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