Vacuum distillation is a method of distillation whereby the pressure above the solution to be distilled is reduced to less than one Atmosphere (unit) causing evaporation of the most volatile liquid(s) (those with the lowest boiling points.) Vacuum distillation is used with or without heating the solution; some distillation processes use both vacuum and thermal action. Strathisla whisky distillery in Keith, Scotland Distillation is a method of separation of substances based on differences in their vapour pressures. ... When expressed as a measurement, an atmosphere (symbol: atm) or standard atmosphere is a unit of pressure roughly equal to the average atmospheric pressure at sea level on Earth. ... The boiling point of a substance is the temperature at which it can change its state from a liquid to a gas throughout the bulk of the liquid. ...

Vacuum distillation works on the principle that boiling occurs when the vapor pressure of a liquid exceeds the ambient pressure (atmospheric pressure above it or pressure in the distillation apparatus.) The process is used when liquids to be distilled have high atmospheric boiling points or chemically change at temperatures near their atmospheric boiling points. Temperature sensitive materials such as complex caratenoids (Beta Carotene) also require vacuum distillation to remove solvents from the mixture while at the same time not damaging the product. Vapor pressure is the pressure of a vapor in equilibrium with its non-vapor phases. ... The boiling point of a substance is the temperature at which it can change its state from a liquid to a gas throughout the bulk of the liquid. ... The boiling point of a substance is the temperature at which it can change its state from a liquid to a gas throughout the bulk of the liquid. ...