Separation of Methanol from Water by Batch Rectification
Consider a binary mixture containing 20 mol% methanol and 80 mol% water. This mixture is to be separated using a batch rectifier operating at mmHg and composed of a still, nine trays, and a total condenser. You can set the values of the heating duty, the reflux ratio, the plateaus, and the condenser hold-ups. The vapor-liquid equilibria calculations are based on either the van Laar or Wilson models. Here, it is found that the choice of the thermodynamic model (to predict the activity coefficients) has very little effect on the composition and temperature profiles.[more]
This Demonstration plots the composition and temperature profiles versus time for the still and distillate. The methanol and water compositions are indicated in the plots by solid and dashed red curves, respectively. A rigorous calculation method, explained in , is used here, with both energy and mass balance equations taken into consideration. In addition, the column is initially operated at total reflux (in order to obtain the initial condition for the subsequent dynamic simulation at finite reflux ratio), and then a distillate is withdrawn from the column (for details, see ).[less]
 U. Diwekar, Batch Distillation: Simulation, Optimal Design, and Control, 2nd ed., Boca Raton: CRC Press, 2012.
"Separation of Methanol from Water by Batch Rectification"
Wolfram Demonstrations Project
Published: December 7 2015