The process of vacuum distillation works to separate two very close boiling compounds under reduced pressure. This occurs when a pressure above the liquid mixture to be distilled is reduced to less than its vapor pressure. This causes volatile liquids to evaporate. Vacuum Distillation can be used with or without heating the mixture.

This modular distillation system created by Koch Modular separates two very close boiling compounds under reduced pressure for a Southeast US aroma chemical producer. The column was packed with 5 beds of Koch Wire Gauze Structured Packing, yielding 80 theoretical stages.