Distillation Techniques
Distillation
➢Theory
• What is distillation used for?
• For what type of compounds?
• What is the basic principle?
➢Experiment
• Procedure
• Equipment
2
Distillation - Theory
• Distillation is a technique used to separate or purify liquids
based on boiling points.
1. Simple distillation
2. Fractional distillation
Simple distillation
3. Vacuum distillation
4. Steam distillation
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1. Simple distillation - Theory
Simple distillation can be used when
• Two components have very different boiling points
Or
• One component is at fairly small amount
small difference
in bp
large difference
in bp
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1. Simple distillation - process
• The heated liquid vaporizes and
rises upward, past the thermometer
into the condenser.
• The vapor is condensed into liquid
and collected in the receiving flask.
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1. Simple distillation apparatus
Thermometer
Boiling
stones
Distillate
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1. Simple distillation apparatus
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1. Simple distillation apparatus
Thermometer
Thermometer adapter
Water out
Water in
Distilling head
Distilling flask
Hot plate
Condenser
Receiving flask
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2. Fractional distillation
Fractional distillation can be used when
• Difference in boiling points is not large
Or
• Highly pure compound is needed
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2. Fractional distillation apparatus
Fractional distillation
Simple distillation
Fractionating
column
(Vigreux
column)
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2. Fractional distillation apparatus
Fractionating
column
Fractionating
column
Graduated
cylinder
Ring stand
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2. Fractional distillation apparatus
Many vaporization-condensation cycles
→ better separation
Fractionating
column
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Explain the process of
separating acetone (bp
56 °C) and toluene (bp
110 °C)
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