Extraction of caffeine from tea lab report

In doing so, the volatile methylene chloride began to evaporate into the surroundings due to the increased room temperature. E — E For each of these solvents, draw the structure and indicate, for an extraction from aqueous medium, whether the solvent will be the top layer or the bottom layer.

Expt 7.6 extraction of caffeine from tea and its purification by sublimation

Why is caffeine more soluble in methylene chloride than in water? For each of these solvents, draw the structure and indicate, for an extraction from aqueous medium, whether the solvent will be the top layer or the bottom layer. We should use proper techniques during the extraction process to get enough amount of extract needed. We did not think it would make much of a difference at the time, but in hindsight, realize that this messes up the mixed-solvent method that recrystallizes the caffeine, thus not getting a higher percent yield because not all of the caffeine precipitated out. Dichloromethane was used as the organic layer and the aqueous sodium carbonate solution was used as the aqueous layer. The residual heat should be enough to complete the evaporation of the dichloromethane. The solution was then mixed with sodium carbonate.

The solution was filtered using a cotton wool into a small separatory funnel. An additional 50 ml of hot water was added to the Erlenmeyer flask with the remaining tea bags and was then immediately decanted and added to the first extracted solution.

The remaining solution was heated briefly until the volatile solvent evaporated, leaving behind solid caffeine. The disintermediation solution was then filtered into a clean Erlenmeyer flask using filter paper and a Hirsch funnel. From the result obtained it was believed that some errors were done during the experiment.

During the extraction, the caffeine might not be fully extracted from the tea. Thus, the caffeine is not extracted in enough amounts for it to achieve the theoretical value.

The remaining organic layer that included the caffeine was dried using anhydrous calcium chloride pellets since they are neutral and unreactive and would not disrupt any further reactions.

The mixture was shaken to ensure that the caffeine will migrate from the tea into the extractant. We extracted some more dichloromethane into the same beaker, but included the emulsion layer and added anhydrous calcium chloride pellets to dry the solution and emulsion layer.

The dried dichloromethane was transferred into small round bottommed flask. When you boil tea leaves, tannins dissolve in the water as well as the caffeine.

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Lab Report: Extraction of Caffeine from Tea Bags Essay Example