A survey of reported compositions along the saturation curve (sat), and compositions of coexisting phases in equilibrium (eq.) for the system 2-propanol-cyclohexane-water is given in Table 59.

Saturation curve The ternary system 2-propanol-cyclohexane-water forms a miscibility gap of type 1. The system was studied five times at the same temperature, 298.2 K. Saturation data are consistent within and between each reference. The exceptions are two points for the cyclohexane-rich phase reported with the evident experimental errors in the paper of Verhoeye² (x₁=0.213 and x₁=0.040). Only one binary system, cyclohexane-water, forms a miscibility gap. The data for this binary system were compiled and critically evaluated in a previously published SDS volume, Ref. 6; the recommended values at 298.2 K are x"₂1.2·10^-5 and x'₃=3.7·10^-4. All experimental solubility and equilibrium data reported at 298.2 K were used for calculation of saturation curve. (Water-rich and hydrocarbon-rich branches were treated together.) These data were described by the equation: x₁=0.475 90+0.056 28 ln(x₂)-0.113 24x₂-058 67x²₂. The parameters were calculated by the least-squares method and the standard error of estimate was 0.0156. Selected points on the saturation curve, calculated by the above equation are presented in Table 60 for selected concentrations of cyclohexane in the mixture and in Figure 30 as calculated binodal curve (solid line).

Phases in equilibrium Compositions of coexisting phases in equilibrium for the ternary system 2-propanol-cyclohexane-water were reported in all references at 298.2 K and tie lines cover the full miscibility gap. The reported plait point, Ref. 3, was x=0.3982 and x₂=0.2776. In the area close to the plait point there are small differences in the direction of tie lines. There is a nearly uniform distribution of alcohol between the phases, the concentration of 2-propanol in the equilibrium phases differs by no more than 0.03 mole fraction. In the water-rich phase, when x₁<0.15, the concentration of cyclohexane is very low, x₂<0.002. The reported equilibrium data sets are consistent with one another and within each data set. The exceptions are two points of the cyclohexane-rich phase reported with evident experimental errors in the paper of Verhoeye² (as discussed above in the description of saturation curve). The data for phases in equilibrium are considered tentative. All experimental tie lines as well as all experimental points, Refs. 1-5, at 298.2 K, are reported in Figure 30 .