Distillation

• Distillation is a laboratory technique employed to separate a homogeneous mixture containing 2 or more liquids with different boiling points. In this method of purification, the liquid organic compound is converted to the vapor state at its boiling point and subsequently condensed back to the liquid state upon cooling
• There are several types of distillation. The more commonly employed are simple, fractional and steam distillation.
• Simple distillation is used in the separation of a volatile liquid from a nonvolatile substance.
• Fractional distillation is used to separate a mixture of miscible liquids that are volatile and with boiling points that are near each other.
• Steam distillation is used in the separation of an organic compound from a solid material using water in the form of steam. The material to be distilled should be immiscible with water which can be readily separated from the water once distillation is complete.
• Reagents and materials:

  Ethyl Alcohol

  Corks and Rubber stoppers

  Boiling chips
• Prepare a 50 mL mixture consisting of 25 mL ethyl alcohol and 25 mL of water.
• Pour the mixture into the distilling flask using a funnel and then add two small pieces of boiling chips. Heat the sample using a low flame initially then gradually increase the flame.
• When the temperature reaches 50°C start recording at 0 mins. Record at 1-minute intervals until only about 10 mL of the mixture remains.
• Prepare 3 flasks labeled 1,2 and 3. Use flask 1 to collect the first distillate. When the temperature reaches 81°C, replace flask 1 with flask 2 and cover flask 1 with a stopper.
• Continue the distillation up to 95°C. At this point, replace flask 2 with flask 3 and cover flask 2 with a stopper.