The technique for the separation of miscible liquids i.e. liquids which dissolve in each other is known as fractional distillation. Fractional distillation is a process of separating the components of a mixture by repeated distillations and condensations. Fractional distillation works on the principal that different liquids boil at different temperature. The miscible liquids boil at different temperature and evaporate at different temperature.
Fractional distillation is also used for the purification of water. It is also used for separating acetone and water. Industrial use of fractional distillation is in petroleum refineries, chemical plants, natural gas processing and separation of pure gases from mixture of gases.