Extraction

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Distillation
Introduction: The recrystallization technique you learned last lab is a method for purifying solids. This week we will learn how to perform a distillation, a method for purifying liquids. Distillation is a common wet-chemical technique for separating organic compounds based on differences in boiling points. Upon heating a mixture of organic compounds, the more volatile compounds (those with the lowest boiling point) will vaporize first (i.e. be converted to gases), leaving the higher-boiling compounds behind in the mixture. By isolating the vapor produced at different temperatures and condensing them (i.e., converting gases to liquids), you can effectively separate and purify compounds based on their boiling points. While there are multiple factors that contribute to the efficiency of distillation, the first, most obvious is the boiling points of the compounds themselves. If one compound is significantly more volatile than another (∆bp > 40 C), then the compounds can be effectively separated in one vaporization step, in a process called simple distillation. However, if the boiling points of the compounds are too similar, then the vapor produced at any given temperature will be a mixture of the two compounds. This time, a process called fractional distillation can be used. Fractional distillation uses a column that allows many small distillations to occur as the vapor ascends the fractional distillation column. Purpose: In this experiment we aim to demonstrate that we can separate two volatile compounds from a mixture due to the different chemical properties of each compound. We will accomplish this by a separation procedure known as distillation, which relies on each compound having a distinct and separate boiling point. Our pure products will be analyzed with gas chromatography to determine the success of the distillation. Glasswares:

-Heat source
-Distillation flask
-Still gead
-Termometer
-Condenser
-Water hose
-Receiver adapter...
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