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Study of Azeotropic Mixtures with the Advanced Distillation Curve Approach



Amelia Hadler, Lisa S. Ott, Thomas J. Bruno


Classical methods for the study of complex fluid phase behavior include static and dynamic equilibrium cells that usually require vapor and liquid recirculation. These are sophisticated, costly apparatus that require highly trained operators, usually months of labor intensive work per mixture, and the data analysis is also rather complex. Simpler approaches to the fundamental study of azeotropes are highly desirable, even if they provide only selected cuts through the phase diagram. Recently, we have introduced an advanced distillation curve measurement method featuring (1) a composition explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), (2) temperature measurements that are true thermodynamic state points that can be modeled with an equation of state, (3) temperature, volume and pressure measurements of low uncertainty suitable for equation of state development, (4) consistency with a century of historical data, (5) an assessment of the energy content of each distillate fraction, (6) trace chemical analysis of each distillate fraction, and (7) corrosivity assessment of each distillate fraction. We have applied this technique to the study of azeotropic mixtures, for which this method provides the bubble point temperature and dew point composition. In this paper, we present the application of the approach to several simple binary azeotropic mixtures: ethanol + benzene, 2-propanol + benzene, and acetone + chloroform.
Fluid Phase Equilibria


Acetone + chloroform, advanced distillation curve, azeotrope, ethanol + benzene, 2-propanol + benzene, phase equilibrium


Hadler, A. , Ott, L. and Bruno, T. (2009), Study of Azeotropic Mixtures with the Advanced Distillation Curve Approach, Fluid Phase Equilibria, [online], (Accessed May 22, 2024)


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Created April 10, 2009, Updated October 12, 2021