The azeotropic behavior of waste water that contains phenol and high concentrated salt in a distillation column

The waste water containing phenol and high concentrated sodium chloride is treated by distillation. Applying a distillation tower, more than 99% phenol is recycled by azeotropic batch fraction. The reflux ratio is optimized to 3 when a fraction column with ten theoretical perfect plates is used. Comparatively, the simple distillation gives dissatisfactory removal of phenol from the waste water.