Fraktionärsäulen

Fraktionärsäulen, also known as fractional distillation columns, are essential pieces of equipment in chemical engineering and laboratories, primarily used for separating mixtures of liquids with different boiling points. The core principle behind their operation is repeated vaporization and condensation cycles, which progressively enrich the component with the lower boiling point at the top of the column.

A typical Fraktionärsäule consists of a tall, vertical column that is heated at the bottom. The liquid mixture is introduced into the column. As the mixture is heated, the components with lower boiling points vaporize and rise. Within the column, there are various internal structures designed to increase surface area. These can include packing materials like Raschig rings or saddles, or specially designed trays or plates. As the vapor rises and comes into contact with these surfaces, it cools and condenses. This condensed liquid then flows back down the column, where it is reheated by the rising vapor, causing a further vaporization of the more volatile components and a condensation of the less volatile ones. This continuous process of vaporization and condensation, occurring multiple times along the length of the column, leads to a separation where the vapor at the top becomes increasingly enriched in the most volatile component, while the liquid at the bottom is enriched in the least volatile component. The separated components can then be collected at the top and bottom of the column.