Jaybee Balilea, Sharmaine Baysic, and Maria Anjelette Patricia Belen
3BIO7, Department of Biology, University of Santo Tomas, Manila, Philippines
Abstract
Extraction is a technique for isolating and purifying organic substances. In this technique, a solution is combined thoroughly with a second solvent that is immiscible with the first solvent. The solute is extracted from one solvent into the other because it is more soluble in the second solvent than in the first.
In this experiment, there were two types of extraction used and these were the Liquid-liquid extraction and Solid-liquid extraction. Liquid-liquid extraction involves a liquid solvent to remove a liquid component from liquid while Solid-liquid extraction allows soluble components to be removed from solids using a solvent. These two types of extraction were used to extract caffeine from tea leaves (Thea sinensis). Caffeine belongs to the group of compounds known as Alkaloids. Alkaloids are a diverse group of compounds that are found in plants and contain basic nitrogen atoms.
There were three methods used in extracting caffeine from tea leaves. These were isolation, purification and characterization of caffeine. Based on the calculations made and with the use of these three methods, a caffeine percentage of .05% and melting point range of standard caffeine and purified caffeine, 27°C and 20°C, respectively were obtained.
Introduction Extraction is a separation technique that involves selectively removing one or more components of a solid, liquid, or a gaseous mixture into a separate phase [1]. The substance being extracted is separated between two immiscible combined phases, and the ratios of its distribution between the phases depend on the relative solubility of the solute in each phase.
A type of extraction, Liquid-liquid extraction is a process used in isolating and purifying products from chemical reactions. This
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