Ternary systems graphical representation

Experimental data on only 26 quaternary systems were found by Sorensen and Arlt (1979), and none of more complex systems, although a few scattered measurements do appear in the literature. Graphical representation of quaternary systems is possible but awkward, so that their behavior usually is analyzed with equations. To a limited degree of accuracy, the phase behavior of complex mixtures can be predicted from measurements on binary mixtures, and considerably better when some ternary measurements also are available. The data are correlated as activity coefficients by means of the UNIQUAC or NRTL equations. The basic principle of application is that at equilibrium the activity of each component is the same in both phases. In terms of activity coefficients this... 

Related Calculations. Graphic representation of liquid-liquid equilibrium is convenient only for binary systems and isothermal ternary systems. Detailed discussion of such diagrams appears in A. W. Francis, Liquid-Liquid Equilibrium, Interscience, New York, 1963. Thermodynamic correlations of liquid-liquid systems using available models for liquid-phase nonideality are not always satisfactory, especially when one is trying to extrapolate outside the range of the data. 

Covering chemical phenomena of 1,2, 3, 4, and multiple component systems, this standard work on the subject (Nature, London), has been completely revised and brought up to date by A. N. Campbell and N. O. Smith. Brand new material has been added on such matters as binary, tertiary liquid equilibria, solid solutions in ternary systems, quinary systems of salts and water. Completely revised to triangular coordinates in ternary systems, clarified graphic representation, solid models, etc. gth revised edition. Author, subject indexes. 236 figures. 505 footnotes, mostly bibliographic, xii -f- 494pp. 536 x 8. 

Representation of (liquid-liquid) equilibrium in an isothermal ternary system by a simple mathematical expression is almost impossible and the best representation of such a case is a graphical one employing triangular co-ordinates. 

The phase behavior of mixtures forms the basis of industrial separations. What makes such separation possible is the fact that when a mixture is brought into a region of multiple coexisting phases, each phase has its own composition. Understanding the phase behavior of multicomponent systems is very important in the calculation of separation processes. In this chapter we review graphical representations of the phase behavior of binary and ternary systems. Since we are dealing with several independent variables, pressure, temperature, and composition, special conventions are used in order to represent information in two-dimensional graphs. 

The acquisition of experimental liquid-hquid equUibria data for solvent-orgaitic mixtures of interest is invaluable for the screening of potential solvents for liquid-liquid extraction. The graphical representation of ternary Uquid-hquid equilibria is most suitably represented through the use of a triangular phase diagram (Fig. 1), where the miscibility characteristics of the system as a function of overall composition are shown. 

Two graphical representations of the isothermal phase diagram of the ternary system including the API, the co-crystallizing agent and the solvent exist, with... 

All of the other cases for the various processes will have some graphical representation. One additional plot is shown in Figure 12-6. The plot is a ternary diagram for the system acetone-water-methylisobutylketone (MIK). This situation represents the data used for a Uquid-liquid extraction. The equilibrium region is under the dome. The straight lines joining the sides of the dome are called tie hnes. Their endpoints represent equilibrium concentrations. 

The interpretation of equation (k) for a ternary or higher-order solution is no more difficult in principle than the interpretation already given for a binary solution. However, every additional component requires the addition of one compositional variable to the free energy of mixing function, and therefore one additional dimension in free energy - composition space. The graphical depiction of a binary system thus requires two dimensions (Gip, X2) that of a ternary system, three dimensions (G, X2, X3), and so on. The graphical representation of multicomponent solutions with c > 3 is virtually impossible, except in projection, and it becomes necessary to rely on strictly fimctional treatments of the properties of state. 

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