Crude Caffeine Extraction Lab Report

In order to obtain crude caffeine from the contents of a tea bag, the processes of extraction was used to remove the caffeine from 2.673 grams of tea leaves. The caffeine was extracted in a separator funnel using dichloromethane and water. The experimental procedure called for three separate extractions using 5 mL of dichloromethane each time. However, one large extraction using 15 mL of dichloromethane was performed due to a misunderstanding while reading the directions. Therefore, the amount of crude caffeine obtained from extraction was very small, and many more impurities were also extracted. The amount of crude caffeine extracted was 0.094 g. When this value is compared to total mass of the tea leaves, the percent yield was determined to be 3.52 %. According to caffeineinformer.com, tea seeped for 5 minutes should contain around 0.047 g of caffeine. When the extracted value is compared to this

After the sublimation technique was performed, no pure caffeine was obtained from the test tube. This resulted in a 0 percent yield when compared to the total mass of the tea leaved at 2.673 g. It also created a 0 percent yield when compared to the 0.094 g of crude caffeine that originally began the sublimation process. No pure caffeine was obtained mainly due to the many errors that occurred during extraction. Furthermore, a slight burnt aroma was protruding from the flask. This led to the conclusion that the act of healing the crude caffeine was flawed. According to Onami and Kanazawa (1996), a 2 g sample of tea leaves should yield about 0.02 - 0.03 g of pure caffeine, and this value matches with the original expected value of 0.047 g of caffeine in 2.673 g of tea. Since no pure caffeine was obtained, a sample of caffeine provided by the lab was used to test the melting point. The melting point of this compound was determined to be 236 - 238 ºC, which matches perfectly with the expected value of 238