Distillation of Alcoholic Beverages
Capalungan, Jann Mark*, Cho, Eunnuri, Cortez, Noelene
and Concepcion, David.
Department of Chemistry, University of Santo Tomas Manila, Philippines
This experiment sought to separate and calculate (in %) the alcohol content of Ginebra San Miguel by distillation and also compare the efficiency of simple and fractional distillation techniques. The experiment is divided into two parts, simple and fractional distillation. Distillate was collected and the remaining sample that didn’t pass through the process of evaporation and condensation is called residue. The residue wasn’t measured because the sample got burned before reaching 100°C temperature. The results show that the ethanol content of Ginebra San Miguel that was separated by simple is 38%. While for fractional distillation, the ethanol content is 46%. The percentage errors for simple and fractional distillation are both 5%. It is also found that fractional distillation is more efficient than simple distillation in terms of decontamination or separation of substances.
Distillation is the process where compounds are purified by separating the more volatile substance from non-volatile or less volatile substance. An example of this is the differences in boiling point. Boiling point is the temperature when the vapor pressure of a liquid-phased compound equals with the pressure exerted on it. This external pressure is usually atmospheric pressure. As the temperature of the liquid increase, the vapor pressure will also increase. And if this case will happen, the vapor pressure will equal to the atmospheric pressure that will cause boiling. Since different compounds have different boiling points, the components often separate from a mixture when the mixture is subjected to distillation.  Also, boiling points can be determined by the process of distillation. In distillation, vapor and liquid compositions are both interest. The compositions of the vapor and liquid are governed by Raoult’s and Dalton’s Laws; provided the vapor and solutions are both Ideal. Raoult’s law states that the vapor pressure of an ideal solution is dependent on the vapor pressure of each chemical component and the mole fraction of the component present in the solution.  While Dalton’s Law states that the total pressure exerted by a gaseous mixture is equal to the sum of the partial pressures of each individual component in a gas mixture.  At any temperature, some molecules of a liquid possess enough kinetic energy to escape into the vapor phase (evaporation) and some of the molecules in the vapor phase return to the liquid (condensation). Equilibrium is set up, with molecules going back and forth between liquid and vapor. At higher temperatures, more molecules possess enough kinetic energy to escape, which results in a greater number of molecules being present in the vapor phase. There are two types of distillation according to separation, the simple and fractional. Fractional distillation is used when the boiling points of chemicals in a mixture are close to each-other, while simple distillation is generally used when the boiling points are significantly different.  In simple distillation, evaporation of a volatile liquid from a solution of non-volatile substances takes place. The water will condense the vapor through the water condenser that will be collected in the receiver. There are cases when the distillate would contain a majority of one liquid but would still contain a little of the second. In order to separate this, another distillation must take place. This repeated distillation is the principle behind fractional distillation wherein it redistills automatically. Automatic redistillation takes place on the apparatus called fractionating column. The vapor produced by the boiling mixture will rise up in the column and will condense when it reaches a certain point. Then it will turn into...
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