Caffeine Extraction Essay

3808 Words16 Pages
Isolation of a Natural Product – Caffeine From Tea References: Fessenden, Ralph J., Fessenden, Joan S., Feist, Patty. Organic Laboratory Techniques. 3rd ed. Pacific Grove: Brooks/Cole, 2001. Print. (61-64, 72-76, 102-107) Jones, Martha O., Ph.D. Laboratory Manual For Chemistry 211. 1998. Print. (42-47) "Material Safety Data Sheet (MSDS) List." ScienceLab.com, Inc. 1997-2005. <http://www.sciencelab.com/msdsList.php>. I. Experimental Objective(s): The objective of this experiment is to extract caffeine from tealeaves with boiling water. Once the caffeine is extracted it will then be isolated from most of the colored compounds by extraction with dichloromethane. After this the crude caffeine will be recrystallized, and then further purify it by sublimation. This will produce a white crystalline solid. II. Experimental Theory: Caffeine is a very common substance and is found in coffee, tea, soft drinks, chocolate, and "stay-awake" pills such as Vivarin. It can be synthesized or isolated from natural sources. Caffeine belongs to a group of compounds known as alkaloids. To be more specific it is a member of the methylxanthines. The basic property of alkaloids comes from the lone pair of electrons found on at least one nitrogen. These compounds are of plant origin, contain basic nitrogen atoms, often have a bitter taste, and usually have a psychological activity. Caffeine is naturally produced by several plants; including coffee beans, guarana, yerba maté, cacao beans, and tea. For the plants, caffeine acts as a natural pesticide. It paralyzes and kills insects that attempt to feed on the plants. In humans, Caffeine acts to stimulate the heart, central nervous system, and the respiratory system. Blood pressure is increased by its use, since heart rate is increased, as is contraction force and volume output. It is a diuretic and has the effect of
Open Document