Ternary mixtures triangular concentration

Analysis of ternary mixtures of certain drugs including salicylamide were studied by plotting the refractive index isotherms of the fused mass and the isotherms of the primary crystals on triangular concentration diagrams. The influence of each factor upon the quantitative determination could be found. In each case there was an area unsuitable for measurement where the isotherms were practically parallel when this was not the case, quantitative determination was possible. Precaution should be taken to prevent loss of highly volatile components (7l). 

Whenever the miscibility of the two phases varies and is dependent on concentration, a triangular diagram is employed (Fig. 2.5). Here the three comers of the equilateral triangle stand for the pure components, the solvent S, the carrier T and the solute C. Each side of the triangle represents binary mixtures, each point within the triangle a ternary mixture. Since the sum of the perpendicular lines of any point in the triangle... 

For ternary mixtures, the limits (12.1.27) define a tie line at the edge of a triangular diagram for two-phase equilibria see, for example. Figure 9.25. But we note that an infinite-dilution tie line is not parallel to the edge, for if it were, the infinite-dilution distribution coefficient would be unity. This means that Q is discontinuous when the infinite-dilution limit passes over to the value of C, for zero concentration. 

The thermodynamics of extraction processes are advantageously described in triangular concentration diagrams since both phases, i.e., raffinate and extract, are ternary mixtures. Mass fractions or molar fractions can be used as a measure for the composition of the phases. Here, x denotes the concentration of the raffinate and y the concentration of the extract. The symbol z stands for the overall concentration of a two-phase system. 

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