Extraction of Caffeine
Extraction of Caffeine from Tea leaves
Casinabe, Antonio Karlo,*Catahay, Jesus Alfonso, Cerdena, O’neil, Cordova, Robelle
Department of Biological Sciences, College of Science
University of Santo Tomas, España Street, Manila 108
Group 4 2MB
Date Submitted: December 13, 2012
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ABSTRACT:
The purpose of this experiment is to extract the amount of caffeine present in tea bags. In this experiment, isolation, characterization and purification of caffeine from tea bags was done through the use of Solvent Extraction and Partitioning method. First, the tea bags were weighed and boiled for five minutes. They were allowed to cool and then they were mixed with dichloromethane. The experimenters performed a technique called single extraction. After the two distinct layers were clearly visible in the separatory funnel, the organic layer or the DCM containing the extracted caffeine in the water was extracted. The process was repeated three times and the collected organic layer (DCM layer) was placed in an Erlenmeyer flask. The combined organic layer was transferred back to the separatory funnel and was washed with sodium hydroxide. After washing, the organic layer was again extracted from the funnel and placed in a beaker containing anhydrous sulphate. The solution was allowed to evaporate to produce crystals of caffeine. The crystals of caffeine produced were combined with ethanol and were placed in a hot water bath until the mixture is clear. The solution was filtered and dried, then weighed. The amount of the pure caffeine was recorded and the percentage yield was computed. Melting point was determined for the characterization of the crystalline caffeine.
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INTRODUCTION
Caffeine extraction is a common technique used in chemical laboratories. It is done to show levels of caffeine present in drinks and foods before releasing them in the market. Since
Casinabe, Antonio Karlo,*Catahay, Jesus Alfonso, Cerdena, O’neil, Cordova, Robelle
Department of Biological Sciences, College of Science
University of Santo Tomas, España Street, Manila 108
Group 4 2MB
Date Submitted: December 13, 2012
-------------------------------------------------
ABSTRACT:
The purpose of this experiment is to extract the amount of caffeine present in tea bags. In this experiment, isolation, characterization and purification of caffeine from tea bags was done through the use of Solvent Extraction and Partitioning method. First, the tea bags were weighed and boiled for five minutes. They were allowed to cool and then they were mixed with dichloromethane. The experimenters performed a technique called single extraction. After the two distinct layers were clearly visible in the separatory funnel, the organic layer or the DCM containing the extracted caffeine in the water was extracted. The process was repeated three times and the collected organic layer (DCM layer) was placed in an Erlenmeyer flask. The combined organic layer was transferred back to the separatory funnel and was washed with sodium hydroxide. After washing, the organic layer was again extracted from the funnel and placed in a beaker containing anhydrous sulphate. The solution was allowed to evaporate to produce crystals of caffeine. The crystals of caffeine produced were combined with ethanol and were placed in a hot water bath until the mixture is clear. The solution was filtered and dried, then weighed. The amount of the pure caffeine was recorded and the percentage yield was computed. Melting point was determined for the characterization of the crystalline caffeine.
-------------------------------------------------
INTRODUCTION
Caffeine extraction is a common technique used in chemical laboratories. It is done to show levels of caffeine present in drinks and foods before releasing them in the market. Since
References: Books: Klein, David. (2012). Organic Chemistry. USA: John Wiley & Sons. Mendoza, Estrella E. (2003). Chemistry. Quezon City: Phoenix Publishing House. Straumanis, Andrei. (2012). Organic Chemistry: a guided inquiry. Boston, MA: Houghton Mifflin Internet sources: http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch14/melting.php http://www.oxford.net/~mavarod/portal/school/caffeine http://www.chemistry.sc.chula.ac.th/bsac/Org%20Chem%20Lab_2012/Exp.4[1].pdf http://www.reference.com/motif/science/caffeine-extraction-from-tea