Residue Curves for Different Activity Coefficient Models

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This Demonstration plots the residue curve passing through a location chosen by the user for a ternary mixture of chloroform, acetone, and methanol at 1 atm.


This mixture presents liquid-phase deviation from ideal behavior, which is taken into consideration by using activity coefficients as predicted by one of the following three models: Wilson, NRTL (non-random two-liquids), and UNIQUAC (UNIversal QUAsi-Chemical).

Residue curve map computation is essential in understanding the distillation behavior of ternary mixtures. Such a calculation also allows the determination of binary and ternary azeotropes, which appear naturally as saddle points, stable nodes, and unstable nodes.


Contributed by: Housam Binous and Ikbel El Glaoui (March 2011)
Open content licensed under CC BY-NC-SA



For more information, see:

M. F. Doherty and M. F. Malone, Conceptual Design of Distillation Systems, New York: McGraw-Hill, 2001.

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