University Chemistry ›› 2020, Vol. 35 ›› Issue (1): 87-91.doi: 10.3866/PKU.DXHX201905002

• Chemistry Laboratory • Previous Articles     Next Articles

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

Liping Song,Yating Wang,Ou Zheng*(),Shuting Wu,Shuying Zhu,Jianzhong Chen   

  • Received:2019-05-06 Accepted:2019-08-05 Published:2019-08-19
  • Contact: Ou Zheng
  • Supported by:


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.

Key words: Physical chemistry, Vapor-liquid phase diagram drawing, Fractionation effect, Temperature compensation


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