SIMPLE AND FRACTIONAL DISTILLATION Ryan Joseph B. Gahol, Mae Anne P. Hamtig, Rio Rosa B. Ibanez, Wilfred Bryan A. Labadnoy and Kyle Nicholas P. Lopez Group 5 2E Medical Technology Organic Chemistry Laboratory
ABSTRACT One vaporization-condensation cycle was used by the group to perform simple distillation to effect a separation. 20 test tubes were calibrated into its .5ml mark to be used as receiver in the experiment. Vodka was put in the pearshaped flask and was heated by an alcohol lamp. As the heating goes on, temperature was critically recorded on every tube will be filled in until it it reached its ceiling boiling point. A flammability test was conducted conducted on the 1 st distillate and last distillate to test what are the components of each distillate. Ethanol and water were found out to be contained in the 1 st distillate for it has produced a flame while water was left on the last distillate.
INTRODUCTION _Alcohols are organic compounds containing ( _Alcohols OH) groups. They are useful in nature, industry and inside the household. It has been used as the essence of wine and also found in alcoholic beverages, cosmetics and drug preparations. It is used as wood alcohol for fuel and as a solvent. It is also used as rubbing alcohol specifically Isopropyl alcohol, which used is to cleanse the skin for injections and cuts. The process of distillation is concerned to the boiling points of the mixtures being separated. Small differences in degrees Celsius can separate mixtures. Distillation is used to separate impurities from liquids. Simple distillation is designed to evaporate a volatile liquid from a solution of non-volatile substances; the vapour is then condensed in the water condenser and collected in the receiver. In this experiment, the group should be able to separate the components of an alcoholic beverage and (2) calculate and determine the percentage ethanol present. Lastly, (3) observe and analyze the process of simple distillation as to its efficiency
EXPERIMENTAL A.Compound tested (or Samples used) Water, Vodka B. Procedure _Simple _ Simple distillation was used as a technique for separation. Before proceeding to the experiment, several test tubes were calibrated down to the 0.5ml mark and were used as a receiver of the distillate. Afterwards, a serological pipet and a
rubber aspirator were used to collect water from the beaker. 0.5 ml of water was transferred into each test tube and calibrated with the use of a marker. Next, a micro-distillation set-up was assembled to portray simple distillation. Fifteen milliliters of Antonov Vodka, was poured into a pear-shaped flask that would undergo simple distillation. The clamps and iron strands was secured and was put into proper places by the members. Every possible insignificant outlet was covered by masking tape to avoid irregularities and deficiencies. The water inlet was opened to let the flow of water occur. Boiling stones were used to avoid overheating and avert bumping. Since the set-up was properly made, with the use of the alcohol lamp, the heating of the distillant was started. The temperature was recorded as it reaches 0.5 ml until the ceiling boiling temperature. Lastly, three drops of the first and last distillate was placed on a watch glass for the flammability test. A lighted match was used to know the flammability of the said distillate.
RESULTS AND DISCUSSION _ Figure Figure 1.0 shows the structure of a simple distillation set-up. set-up. In simple distillation, all the hot vapors produced are immediately channeled into a condenser that cools and condenses the vapors. Therefore, the distillate will not be pure its composition will be identical to the composition of the vapors at the given temperature and pressure, and can be computed from Raoult's law. As a result, simple distillation is usually used only to separate liquids whose boiling points differ greatly (rule of thumb is 25 °C), [13] or to separate liquids from involatile solids or oils. For these cases, the vapor pressures of the
components are usually sufficiently different that Raoult's law may be neglected due to the insignificant contribution of the less volatile component. In this case, the distillate may be sufficiently pure for its intended purpose.
5.
Inadequately clamping the apparatus can be dangerous. Over clamping can be a problem, since it causes stress in the apparatus.
Computations Table 1.0 shows an increase in temperature for every 0.50 ml of collected vapor. As the temperature become constant and maintains a constant slope in the graph, it manifests the presence of ethanol in the sample where it is most concentrated. During the flame test, there is a presence of alcohol from the 1st test tube when it produces a blue flame. When there is no flame produced, ethanol is not present in the last test tube. Figure 1.1 shows the relationship of temperature to the volume of vapor collected from the sample. There is an evident increase in the temperature as every 0.5 ml distillate was dropped. The highlighted part indicates where the concentration of alcohol from the beverage is strongest. An azeotrope is a mixture of components in such a ratio that its composition cannot be changed by simple distillation because the vapor has the same ratio of constituents as the liquid. Because composition is unchanged, azeotropes are also called constant boiling mixtures. Table 1.1 shows that first distillate evenly produces a blue flame because the initial drop contains ethanol which is highly flammable. The last distillate we collected was only pure water that results into absence of a flame when tested. This is because the ethanol present was already distilled during the early distilling process.
1. Percentage of ethanol: % Alcohol =
Vf-Vi x 100 Vs
% Alcohol = 5.0 ± 3.5mL x 100.00 = 10% 15mL 2. Percentage loss: %100 = VS ± (Vresidue + Vdistillate) x 100 %100 = VS ± (Vresidue + Vdistillate) x 100 = 15 ± (4.1 +10) x 100 15 = 15-14.1 x 100 15 = 6% less
REFERENCES From books LeMay, H., Beall, H., Robblee, K., & Brower, D. (1996). Chemistry: Connections to Our Changing World. Upper Saddle River: Prentice Hall. L. G. Wade, Jr. (2005) Organic Chemistry:6th edition. Upper Saddle River: Prentice Hall. From the internet
Listed below are the following possible sources of error: 1.
Parallax reading of temperature
2.
Inaccurate calibrating 0.5 ml test tubes
3.
Distillate might have vaporize during the experiment before it was tested to flammability test.
4.
Placing the thermometer too high will lead to a low value for boiling point.
4.1.SimpleDistillation http://wapedia.mobi/en/Distillation?t=5. 07/15/10 Ch E 514 - Intermediate Chemical Engineering Calculations chemeng.nmsu.edu/ChE307/notes/Complex%20D istillation.pptx 07/15/10 Distillation http://www.chemistry.sjsu.edu/straus/FAQ/Techni que%20FAQ/DistillationFAQ.htm _07/15/10
