Extraction of alcohol from beer by distillation.

METHOD & OBSERVATIONS

• Health & Safety precautions were taken; this includes wearing lab coats and goggles in order to avoid harm to one’s body or surroundings.
• The apparatus was set up to carry out the experiment.
• A spatula was used to insert anti-bumping granules into the boiler (these help the distribution of heat throughout the solvent).
• 250cm3 of beer was measured and poured into the boiler by a funnel.
• The boiler was placed into the flameless heater, which was switched on.
• After some time, the beer began to boil, and vapours began to rise. The vapours pass through the fractional distillation column and into the condenser, where it cools down and turns back into the state of liquid.
• The liquid pours down into the round bottom flask inside a bucket with ice, to maintain its liquid state.
• The thermometer was constantly observed, this is because the boiling point of the beer is 78°C and the boiling point of water is 100°C, therefore we must make sure we do not exceed the temperature over the beer’s boiling point, as our desired product is only the alcohol.
• When the water molecules vaporised and began to pass the distillation flask, it quickly condensed and poured back down into the boiler.
• After some time, the boiling had stopped; this is a sign that there is no more alcohol left (because alcohol expands and causes the bubbles), and so the power of the heater was turned off.
• The alcohol in the round bottom flask in the bucket was collected and measured into a measuring cylinder, and results were recorded.

TESTING FOR ALCOHOL

• The measuring cylinder containing the pure alcohol was taken over to the fume cupboard.
• A dropping pipette was used to drip to drip the alcohol into a watchglass (pipette was held vertically for consistent drop-size).
• A lit match was engaged with the alcohol, erupting a blue flame; proof of alcohol.
• An alternative way of confirming the test for alcohol is by recognising the scent of alcohol.

LABELLED DIAGRAM

RESULTS

Calculations on beer experiment:

• Volume of beer (Tennenent’s Super Strong Lager) = 25Ocm3
• Percentage of alcohol by volume/volume=9%
• Theoretical yield or maximum yield =(9/100)x beer volume = (250)

=  9/100 x 250 = 22.5cm3

• Volume of alcohol collected by distillation of beer = 16cm3
• Percentage yield of alcohol from beer = (actual yield/theoretical yield) x 100

= 22.5/16 x 100 = 71.1%

CONCLUSION

In conclusion, pure alcohol was successfully produced by the fractional distillation method; however we were not able to collect the full theoretical yield due to the error factors.