Azeotropes for Ternary Systems
Case of Acetone - Chloroform - Methanol System
Author's Data: Housam BINOUS
Department of Chemical Engineering
National Institute of Applied Sciences and Technology
Tunis, TUNISIA
Email: binoushousam@yahoo.com

Acetone = component 1
Chloroform = component 2
Methanol = component 3

Gas Constant and Total Pressure

R = 1.987; P = 760;

Vapor Pressure Using Antoine Equation

A1 = 7.11714; B1 = 1210.595; C1 = 229.664;
A2 = 6.95465; B2 = 1170.966; C2 = 226.232;
A3 = 8.08097; B3 = 1582.271; C3 = 239.726;

PS1 = 10^(A1 - B1/(C1 + T));
PS2 = 10^(A2 - B2/(C2 + T));
PS3 = 10^(A3 - B3/(C3 + T));

Binary inetraction Parameters and Activities for Wilson Model

l12 = 116.1171; l21 = -506.8519; 
    l13 = -114.4047;
l31 = 545.2942; l23 = -361.7944; 
    l32 = 1694.0241;
V1 = 74.05; V2 = 80.67; V3 = 40.73;

X3 = 1.  - X1 - X2;

R = 1.987; P = 760;

A12 = 
        V2/V1 Exp[-l12/(R*(273.15 + 
                      T))];
A13 = 
        V3/V1 Exp[-l13/(R*(273.15 + 
                      T))];
A32 = 
        V2/V3 Exp[-l32/(R*(273.15 + 
                      T))];
A21 = 
        V1/V2 Exp[-l21/(R*(273.15 + 
                      T))];
A31 = 
        V1/V3 Exp[-l31/(R*(273.15 + 
                      T))];
A23 = V3/V2 Exp[-l23/(R*(273.15 + T))];

GAM1 = 
        Exp[-Log[X1 + X2*A12 + X3*A13] + 
            1 - (X1/(X1 + X2*A12 + X3*A13) + 
                X2*A21/(X1*A21 + X2 + X3*A23) + 
                X3*A31/(X1*A31 + X2*A32 + 
                        X3))];
GAM2 = 
        Exp[-Log[X1*A21 + X2 + X3*A23] + 
            1 - (X1*A12/(X1 + X2*A12 + X3*A13) + 
                X2/(X1*A21 + X2 + X3*A23) + 
                X3*A32/(X1*A31 + X2*A32 + 
                        X3))];
GAM3 = 
        Exp[-Log[X1*A31 + X2*A32 + X3] + 
            1 - (X1*A13/(X1 + X2*A12 + X3*A13) + 
                X2*A23/(X1*A21 + X2 + X3*A23) + 
                X3/(X1*A31 + X2*A32 + X3))];

Calculation of the composition and temperature of the four Azeotropes: 3 binary and a ternary azeotropes

Y1 = X1*PS1*GAM1/P;
Y2 = X2*PS2*GAM2/P;
Y3 = X3*PS3*GAM3/P;

FindRoot[{Y1 == X1, Y2 == X2, 
        P == X1*PS1*GAM1 + X2*PS2*GAM2 + X3*PS3*GAM3}, {X1, 0.3}, {X2, 
        0.4}, {T, 40}]

FindRoot[{Y1 == X1, Y2 == X2, 
        P == X1*PS1*GAM1 + X2*PS2*GAM2 + X3*PS3*GAM3}, {X1, 0}, {X2, 
        0.4}, {T, 57}]

FindRoot[{Y1 == X1, Y2 == X2, 
        P == X1*PS1*GAM1 + X2*PS2*GAM2 + X3*PS3*GAM3}, {X1, 0.3}, {X2, 
        0}, {T, 57}]

FindRoot[{Y1 == X1, Y2 == X2, 
        P == X1*PS1*GAM1 + X2*PS2*GAM2 + X3*PS3*GAM3}, {X1, 0.3}, {X2, 
        0.6}, {T, 63}]