(under subclass 350) Processes wherein the rectification zone is under a pressure greater or less than atmospheric pressure.
(1) Note. The use of pressures varying from atmospheric changes the relative volatility of the components of the distilland which may lower the boiling point of the respective components of the mixture thereby increasing the ease of separation of the components of the distilland.
SEE OR SEARCH CLASS
196, Mineral Oils: Apparatus,
114, for vaporizers adapted to distill mineral oil under reduced pressure.
203, Distillation: Processes, Separatory,
73+, and 91+ for a distillation process utilizing pressure or vacuum.
