EXTRACT

HOW MUCHEXTRACTLINKSCONTACT


  • Place 2g instant coffee and 2g Na2CO3 in 100mL of water in a beaker.
  • Heat the solution with occasional stirring for 5-10 mins.
  • Cool the solution and decant it into a separatory funnel.
  • Add 10 ml of methylene chloride and gently mix the two layers by inverting the funnel several times for about 5 mins. Vigorous shaking of the funnel should be avoided as it will result in the formation of an emulsion between the two layers.
  • Drain out the lower methylene chloride layer from the separatory funnel into an Erlenmeyer flask leaving behind any emulsion that forms.
  • Repeat the extraction with another 5 mL of methylene chloride and add the two extracts together.
  • Add a small amount of MgSO4 to the flask and shake it well. A clear solution indicates that it is dry.
  • Transfer the dry solution to a weighed 25 mL RB flask and evaporate the solvent on the rotary evaporator.
  • Determine the weight of the crude product and recrystallize it from ethanol or acetone. And there you have some pure caffeine!

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