distilling

Distilling is a physical separation process based on differences in volatility among components of a liquid mixture. When heated, more volatile components vaporize first; the vapor is cooled and condensed, yielding a distillate enriched in the more volatile substance while less volatile components remain.

Distillation has ancient roots and evolved into essential modern techniques used in laboratories and industry. Variants include simple, fractional, vacuum, and steam distillation, each suited to different boiling-point relationships and material sensitivities.

Basic equipment includes a distillation flask, heat source, condenser, and receiving vessel. A fractionating column increases separation by creating many theoretical plates; vapors rise, condense, and re-vaporize as needed during fractional distillation.

Simple distillation separates liquids with widely different boiling points; fractional distillation handles closer point separations. Vacuum distillation lowers pressure to reduce boiling temperatures for heat-sensitive compounds, while steam distillation uses water vapor to carry volatile, heat-sensitive substances.

Applications range from beverage production and essential oil extraction to purification of solvents and refinery processes. In industry, atmospheric and vacuum distillation are used to separate crude oil into fractions; in laboratories, distillation purifies chemicals.

Limitations include azeotropes that resist separation, energy requirements, and safety considerations for flammable vapors and high temperatures. Legal frameworks govern the production of distilled beverages in many jurisdictions.