Destillasjon

Destillasjon is a physical separation process in which components of a liquid mixture are separated based on differences in their volatility. By heating a liquid to produce vapor of the more volatile components and then cooling the vapor back to liquid, a distillate is collected while less volatile components remain in the residue. The process is widely used to purify liquids, separate mixed liquids, and concentrate desirable fractions.

The core principle is that components with lower boiling points vaporize more readily than those with higher boiling points. A distillation setup usually includes a heating source, a vessel (pot or still), a condenser to cool and liquefy the vapor, and a receiver for the collected distillate. In many cases a fractionating column is attached between the pot and the condenser to improve separation by providing repeated vapor-liquid contact, which increases the effective separation of close-boiling components. Important limitations include the presence of azeotropes, which can form constant-boiling mixtures, and the high energy demand of the process.

Variants of distillation include simple distillation, fractional distillation, vacuum distillation, and steam distillation. Vacuum distillation lowers boiling points by reducing pressure, useful for heat-sensitive substances. Steam distillation uses steam to carry volatile compounds, common in essential oil extraction, while industrial distillation often employs long fractionating columns and large-scale equipment.

Applications span beverage production (spirits), purification of solvents and chemicals, petroleum refining (fractional distillation of crude oil into fractions), essential oils, and desalination in some setups. Destillasjon has ancient roots with modern industrial methods developing in the 19th and 20th centuries to enable scalable, efficient separations.