Simple Distillation Residue Curves for a Mixture of Chloroform and Acetone at 760 mmHg

The vapor-liquid equilibrium behavior of a binary mixture of chloroform and acetone at 760 mmHg can be obtained using the Wilson model and a modification of Raoult's law.

This mixture exhibits a maximum boiling azeotrope, whose composition is 66.13% chloroform mole fraction.

The simple distillation residue curve is the solution of the following differential-algebraic equation:

, , and ,

where is the warped time, is the chloroform mole fraction in the still at , is the equilibrium constant, and is the initial ethanol composition in the still.

Since a negative azeotrope exists for this mixture, the still has the azeotropic composition for large (i.e., ), independent of the initial composition in the still.