Distilllation

• Simple distillation


  1. Evaporate the liquid by heating

  2. Condense the vapor back to a liquid by cooling
• Simple distillation


  • Consists of two stages: evaporation and condensation
• There is another type of distillation called fractional distillation
• Solution


  Liquid with a dissolved solid
• Simple distillation can be used to produce drinking water from sea water
• A great deal of energy is required for simple distillation
• Generally, simple distillation is not used to produce drinking water, other techniques are used instead
• Fractional distillation


  A method used to separate a mixture of different liquids based on their different boiling points
• Fractional distillation


  • Requires a mixture of liquids with different boiling points
  • Uses a fractionating column containing glass beads to increase the separation of the liquids
• Fractional distillation process


  1. Heat the mixture

  2. Vapors with lower boiling point rise up the fractionating column first

  3. Vapors condense and drip back into the flask

  4. Repeated evaporation and condensation increases the concentration of the lower boiling point liquid

  5. Thermometer measures the temperature, which rises and then plateaus at the boiling point of the first liquid

  6. First fraction collected

  7. Temperature rises again, plateauing at the boiling point of the second liquid

  8. Second fraction collected
• If the two liquids have very similar boiling points, it is much harder to separate them and multiple rounds of fractional distillation may be required