Distillation
Fractional and Simple Distillation
Chem 236 Lab 6
Zac Goertz
Mario Morones
Shane Jones
Stefan Hinote
11/25/2013
Introduction: The purpose of this lab is to use simple and fractional distillation to separate a
mixture of toluene and hexane from each other. Simple distillation involves a simple setup
involving the flask, distillation head, condenser, vacuum takeoff adapter, and a graduated cylinder
to collect condensate. Fractional distillation is the same thing, but with an added fractionating
column wrapped in an insulating jacket of glass wool and tinfoil. After slowly heating the roundbottom flask in a sand bath, the resulting gases will collect in the condenser, and after being cooled
with circulating water, condense into the distilled product to be collected for gas chromatography
testing. Gas chromatography testing will show how effective the distilling process was in
separating the hexane and toluene.
Experimental Procedure6A
1) Assemble distillation apparatus with and without fractionating column (simple distillation
and fractional distillation)
2) Insulate fractionating column, bulb thermometer directly below side port
3) Add boiling stones to round bottom flask
4) Add 15.0mL unknown mixture to flask
5) Start water circulation on condenser (water inlet = lower, against gravity, water outlet =
higher)
6) Heat flask with hotplate in sand bath
7) Regulate temp so drops of distillate fall at rate of one drop per five seconds into graduate
cylinder / vial. (Heat will have to be readjusted through distillation as proportions of
unknown mixture and vapor will be changing)
8) Once graduated cylinder distillate volume reaches 1.0mL, record temp, switch to labeled
vial, collect 1.0mL sample and temp, repeat until round bottom flask is almost empty but not
dry.
9) Turn off heat and raise distillation apparatus off sand bath and hot plate.
Results Simple Distillation
Temperature C
Sample Volume mL
GC Peak One %
GC Peak Two %
72
1.0mL S1
90.63%
9.269%
74.5
1.0mL
76
1.0mL S3
83.34%
16.58%
80
1.0mL
86.5
1.0mL S5
60.79%
39.14%
92
1.0mL
101.5
1.0mL S7
7.336%
92.60%
103.5
1.0mL
104
1.0mL S9
0.569%
99.37%
Compound A BP ~ 74C
Compound B BP ~104C
Results Fractional Distillation
Temperature C
Sample Volume mL
GC Peak One %
GC Peak Two %
62
1.0mL F1
94.68%
5.220%
56
1.0mL
61
1.0mL F3
95.48%
4.431%
60
1.0mL
62
1.0mL F5
94.18%
5.745%
61
1.0mL
61
1.0mL F7
89.09%
10.83%
94
1.0mL
95
1.0mL F9
0.398%
99.56%
96
1.0mL
96
1.0mL F11
0.062%
99.90%
Compound A BP ~60C
Compound B BP ~96C
Experimental Equipment:
Fractionating Column wrapped with glass wool and aluminum foil
Distillation Head
Vacuum take off adapter
Condenser with plastic tubing to run water in and out.
Graduated Cylinder with small 1ml conical vials.
Round Bottom flask.
Automatic Pipette
Heating plate
Sand Bath
Thermometer
Discussion/Conclusion: The results of the experiment showed that fractional distillation
was immensely effective at separating the two compounds present in the mixture. Starting off
reasonably slow, with the composition roughly at 94.68% hexane and only 5.22% toluene,
fractional distillation was able to separate so effectively that the end purity of toluene was 99.90%,
with almost all of the hexane gone from the solution. This can be attributed to a steady boiling
point that did not oversaturate the distilled product with too much of the product with a higher
boiling point. The simple distillation produced good results as well. Starting with 83.34% hexane
and only 16.58% toluene, the end purity of the toluene collected was 99.39%. The differences in
this experiment were minimal, but the fractional distillation produced a product that was slightly
purer than the simple distillation, and would probably make a larger difference in a large scale
distillation.