Temperature Compensation Method to Solve the Fractionation Effect in the Experiment of Binary Vapor-Liquid Equilibrium System Phase Diagram

In this paper, the device for phase diagram development experiment has been modified, which can be used to measure the boiling point and dew point of vapor-liquid equilibrium system simultaneously. In addition, the vapor-liquid phase diagrams of cyclohexane-ethanol under the conditions of no heat preservation, heat preservation and temperature compensation are drawn and compared. Results show that there is a great difference between the temperatures of boiling point and dew point both for the vapor-liquid equilibrium system with the simple heat preservation or without the heat preservation, and the vapor-phase lines based on the boiling point temperature are seriously distorted. With the temperature compensation for the system, the two vapor-phase lines according to the boiling point and the dew point temperature are in good agreement, which means the problem of vapor-phase fractionation effect has been solved.