Simple Distillation, Rectification and Partial Condensation

1 Concepts of Simple Distillation, Rectification and Partial Condensation 

Distillation is a process for the thermal separation of liquid mixtures. The process may be used when the boiling points of the components in the mbcture are significantly different, provided the substances are thermally stable under the operating conditions. 

The following is typical for a distillation process by supplying heat, approximately isobarically, some of the liquid mixture is vaporized. The vapor is then distilled off and condensed after separation from the remaining liquid mixture, forming a second phase, the vapor phase. The low-boiling substances of the mixture are enriched in the vapor phase (case relative volatility )  

The selective vapor phase generally has a different composition to the liquid phase (an exception being an azeotropic mixture). By separating the vapor phase from the remaining liquid mixture a partial separation is carried out and since the vapor phase is enriched with the more volatile components, the less volatile components are concentrated in the distillation residue. 

In the process of partial condensation some of the vapor mixture is condensed by the removal of heat. Low-boiling components are therefore enriched in the remaining vapor, while the condensate of the additional selective phase contains the 

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