Principle

In countercurrent distillation (rectification) using a column,
the rising vapour can enter into interactions with the condensate.
In this manner, a fractional distillation, i.e. a distillation in
several steps for the separation of substances with similar boiling
points, can be performed in a single apparatus. If bubble tray
columns are used condensate can be removed from the individual
bubble trays.

Tasks


Investigate the mode of operation of a fractionating tower on a
two-stage bubble tray column. Distil a mixture of three n-alcanes
first with total reflux and then without any reflux.

Subsequently, examine and compare the initial mixture, the sump
product, the head products and the condensates of both trays gas
chromatographically.


What you can learn about


Bubble tray column

Rectification

Continuous and discontinuous distillation

Vapour pressure

Vaporisation

Condensation

Raoult’s law

Gas chromatography


Necessary accessories


Precision balance 620g/0.001g


Software included. Computer not provided.