University of Sto. Tomas Faculty of Pharmacy Department of Pharmacy
im le Distillation Casao, Elaine Andrea S.
Abstract
This experiment aimed to separate the alcohol and water existent within a certain amount of vodka, and to determine the amount of Ethanol in the vodka and the percentage loss of Ethanol that has occurred during the distillation process. There are several types of distillation, which would be discussed later, however, this laboratory report will focus more on the simple distillation of vodka. Simple distillation involves the principle of relative volatility and boiling points, which require the substances to have a huge difference in their boiling points to be separated. The substances that has been separated are Ethanol and water in the vodka sample. The presence of ethanol and water has been indicated through a flame test. The ethanol was present at the 1 st distillate up to the 5 th and last distillate, however, however, the flame on the 1 st distillate lasted longer than the 5 th which simply means that the ethanol content on the 5 th distillate were decreased. The calculations for the percent Ethanol in the vodka is 11.33% and the percentage loss is 70%.
Introduction
Distillation is the process of separating two or more liquids which have large relative volatility between the two substances and a big difference between their boiling points. However, the more different the substances are in their volatility and boiling points, the easier it is to separate the components in the mixture. There two phases included in this procedure, one is the liquid phase which resulted from the condensation part, and the gas phase which is usually called the vapor that resulted from the evaporation part of the method due to the boiling of the aqueous solution. There are several types of distillation, namely, simple distillation, fractional distillation, vacuum distillation and the stem distillation. Simple distillation has the simplest set-up than the latter types of distillation. This involves separation of a volatile liquid and a non-volatile liquid that have a big difference in their boiling points. Fractional distillation is almost the same to the function of the simple distillation, however, it has an addition of a fractional distillation column, which contains a substance occupying a high surface area for a more efficient separation of the two or more liquids in a mixture. Vacuum distillation is also similar to simple distillation in terms of function, however the substance involved in the mixture tend to decompose when boiled at high temperatures, hence a vacuum is put over the liquid to prevent the decomposition of the substance in the process of separation. While, steam distillation, on the other hand, is also similar to simple distillation, however this involves substances that are slightly soluble in water, that have a tendency to decompose at higher temperatures, and that have terrible bumping when used in a vacuum distillation. Since steam lets the substance boil at a lower temperature, steam is used instead of a direct flame from from an alc alcoho oholl lam .
Methods
The experiment required a quick-fit apparatus, vodka, alcohol lamp, and boiling stones. Simple distillation was the kind of distillation assigned to the group. This form of distillation separates components through a simple process of evaporation and condensation. Simple distillation is possible due to different boiling point of components in a mixture. The first step in this experiment requires preparation of materials. This involves labeling and calibrating test tubes to 0.5mL that will be used to receive the distillate. Simultaneously, 3 members of the group carefully prepared the set-up. This set-up is prepared with the use of two iron stands, one supports the condenser, and one holds the quick-fit distilling flask. Under the quick-fit distilling flask is the alcohol lamp, above the flask is a thermometer and on its distal portion is the attachment of the condenser. On the end of the condenser most proximate to the distilling flask is the water outlet, while the projection on the other side is for the water inlet. After the preparation of the set-up,3 pieces of boiling stones are introduced into the flask that contains 30 mL of vodka. Then an alcohol lamp was lit up and placed directly below the distilling flask. The lamp requires rotation in order to control the distribution of heat to the set-up. It is also important to record the temperature of the first drop and so as every distillate received by the 0.5 mL calibrated test tubes.
Subsequent to the experiment performed. Test for flammability was executed. This test requires a watch glass, a source of flame (match), and the 1stand last distillate. Placing 3-5 drops of distillate from the 1st test tube on a watch glass and the application of flame to it from a lightened match did this procedure. The previous process was repeated to the last test tube. The presence of flame pertains that there is ethanol in the distillate.
Results and Discussions
Five distillates were collected throughout the experiment. Figure no.1 shows the data collected. mL
0C
1st
0.8
78
2nd
0.6
77
3rd
0.7
78
4th
0.5
75
5th
0.8
78
Figure 1: Data Collected The content of the 1st test tube and the last test tube was tested for their flammability. Both produced fire, meaning the distillate collected from the first test tube and the last test tube contains ethanol. Figure 2: The Simple Distillation Set Up -
COMPUTATIONS For percent ethanol: % ethanol = % ethanol =
3.4 3
100
100
= 11.33% For percent loss: % loss = % loss =
−(+) 3−(3.4+2) 3
100 100
= 18.67%
Conclusion The percentage loss shows the amount of spilled liquid during the span of the experiment. The % loss may also be an indication of error that occurred in the experiment and since the experiment yielded 3.33% loss, it is reasonable and expected, yet there might be errors that occurred that might be improved in the succeeding experiment like for example the modulation of heat or lack of temperature control, reading of temperature from the thermometer, the attachment or tuning of the instruments used that could have allowed proper removal of vapor from the instrument. Allin all, the process of distillation is an effective way of separating and/or purifies liquid mixture.
