distillation summary

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Below is the article summary. For the full article, see distillation.

A laboratory distillation apparatus demonstrating desalination of water. In the distillation flask, salt water is boiled to produce water vapour, or steam, while the salt remains in the liquid solution. The vapour rises through the top of the flask and passes into the condenser, which consists of a glass tube within a larger tube. Cold water flows through the space between the tubes, cooling the vapour in the inner tube so that it condenses and flows into the receiving flask.

distillation, Vaporization of a liquid and subsequent condensation of the resultant gas back to liquid form. It is used to separate liquids from nonvolatile solids or solutes (e.g., water from salt and other components of seawater) or to separate two or more liquids with different boiling points (e.g., alcohol from fermented beers and wines). Many variations have been devised for industrial applications. An important one is fractional distillation, in which vapour from a heated liquid mixture is contacted by a series of trays and condensed liquid as it rises through a vertical column. The most volatile fraction of the mixture emerges from the top of the column, while less volatile fractions are withdrawn at lower points. In petroleum refining, this method is very efficient for removing naphtha, kerosene, and gas oils from crude oil.