Yeast Distillation Lab Report

McArthur Mock 9/14/16

Pre-Lab 3

Chem 3152 – 014 Fall 2016

Fermentation and Distillation

Objective:

The purpose of this experiment is to produce ethanol in an anaerobic-based environment through fermentation of yeast. After that, the solution made fro this will be further distilled to create a very high percentage solution of ethanol.

Techniques and Reactions:

• Ethanol Fermentation: the process of chemically breaking down bacteria/yeast in an anaerobic environment, which in turn releases CO2.

• Distillation: the purification of an organic liquid compound utilizing each’s boiling points, along with evaporation and condensation.

Reactions:

Sucrose (anaerobic isolation) cellular energy + CO₂ + ethanol (distillation) High

To assemble this apparatus all of the following will be needed: a jacketed condenser, thermometer, 50 mL kjeldahl shaped flask, 100 mL kjeldahl flask, vacuum adapter, distilling column and a connecting adapter. Next, clamp the glass joints to the ring stand to properly secure the apparatus. Once finished with assembly, proceed to ad 60 mL of the fermented yeast prepared at the last experiment lab to the 100 mL flask and also add a small spin vane. Then, carefully place the flask into the sand bath. After this is done, let the water run that’s connected to the condenser slowly. At the same time, also slowly heat up the solution. For the experiment to be the most successful it’s important to slowly heat the flask because properly heating the flask will lead to a high percentage purity ethanol distillation. You can also add aluminum foil to the bottom of the flask, as this will help with the reflux process. Keenly observe the reflux process as you continue to slowly heat up the solution. Once the reflux line starts to get nearer to the connection adapter, record the temperatures. Once there’s a good amount of distillate in the 50 mL flask, go ahead and collect 2 to 3 mL of the distillate and transfer this into a labeled vial and give to your TA so he/she can measure out the distillate using a 1000 mL Eppendorf pipette. Lastly, weigh the solution on an analytical balance and record the weight. Using the weight recorded, calculate the density and compare to the density table listed below to determine the percent