Extraction Of Crude Caffeine From Tea Using Liquid-Liquid Extraction (Presentation)

EXPERIMENT 5Extraction of Crude Caffeine from Tea using Liquid-Liquid ExtractionCHEM LAB1A GRP 4INTRODUCTIONExtraction of Crude Caffeine from Tea using Liquid-Liquid ExtractionCHEM LAB1A GRP 4One of the most consumed caffeine-containing beverage on the planet is tea. The caffeine (C8H10N402 ) found in it is white, crystalline methylxanthine and a member of a class of compounds called as alkaloids (Wang,2011).Figure 1. Caffeine bond line structureAlkaloids, such as caffeine, are often physiologically active in humans and are known central nervous system stimulants and diuretics (Wang, 2011). Acidic tannins, undecomposed chlorophyll, cellulose and pigments are also found in tea leaves. In order to extract caffeine from tea leaves, caffeine must be present as the free base (Amrita, 2013). In order to do so,a difference in solubility must occur to separate the tannins into the aqueous layer. Sodium carbonate is added to the extraction medium to ensure that the acidic components in the tea leaves remain water soluble and that caffeine is the free base.Objectives:1.Isolate crude caffeine from brewed tea by liquid-liquid extraction using hexane and diethyl ether extracting solvents.2.Compare the extraction efficiency of the two extraction solvents.3.Compare the extraction efficiency of crude caffeine by single and multiple extraction.MATERIALS AND PROCEDURESExtraction of Crude Caffeine from