IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Glass Ball as Bullet Solubility System: 2-Propanol with Hexane (n-hexane) and Water
Components:
   (1) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail
   (2) 2-Propanol (isopropanol, isopropyl alcohol); C3H8O; [67-63-0]  NIST Chemistry WebBook for detail
   (3) Hexane (n-hexane); C6H14; [110-54-3]  NIST Chemistry WebBook for detail
Evaluator:
   A. Skrzecz, Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland (1996.05)

 Critical Evaluation:
      A survey of reported compositions along the saturation curve (sat), and compositions of coexisting phases in equilibrium (eq.) for the system 2-propanol-hexane-water is given in Table 61.

Saturation curve
   The system 2-propanol-hexane-water forms a miscibility gap of type 1. Compositions along the saturation curve was reported only in Ref. 1 at 298 K. Only one binary pair of components, hexane-water, is partially miscible. The data for this system were compiled and critically evaluated in a previously published SDS volume.3 The recommended values of mutual solubility of hexane-water system 298.2 K are x'2=0.999 53 and x"2=2.3·10–6. Two compositions in equilibrium at 331.2 K2 were reported to be binary mixtures (concentration of the third component became equal 0.0). It seems that the analytical method used (gic) did not detect low concentrations of water and therefore these data are treated as inaccurate.

Phases in equilibrium
   Compositions of coexisting phases in equilibrium for the ternary system 2-propanol-hexane-water were reported in both references. There is no distribution of alcohol between the phases at 298.2 K1 (concentration of 2-propanol expressed in mole fractions is practically constant). Composition of a plait point obtained graphically by the authors of Ref. 1 is equal to x1=0.416 and x2=0.240. Equilibrium data at 298.2 K are in agreement with data on the saturation curve and are also consistent with other ternary systems 2-propanol-hydrocarbon-water reported in Ref. 1. The larger miscibility gap and different direction of tie lines at 331.2 K than those at 298.2 K further show that the data of Ref. 2 are inaccurate. The data of Vorobeva and Karapetyants1 at 298.2 K are treated as tentative and they are presented in Fig. 31 .

 Experimental Data:   (Notes on the Nomenclature)
TABLE 61. Summary of experimental data for the system 2-propanol-hexane-water
AuthorT/KDataTypeReference
Vorobeva and Karapetyants, 1967298sat. (11), eq. (12)1
Morozov et al., 1978331eq. (6)2
 View Figure 1 for this Evaluation

Notes:
Table 61  Number of experimental points in parentheses.

 References: (Click a link to see its experimental data associated with the reference)
   1  Vorobeva, A.I.; Karapetyants, M., Kh., Zh. Fiz. Khim. 41, 1984-9 (1967).
   2  Morozov, A.V.; Sarkisov, A.G.;Turovskii, V.B.; Ilyaskin, V.I., Dep. Doc. VINITI 102-78, 1 (1978).
   3  Shaw, D.G., ed., Solubility Data Series, Vol. 37, Hydrocarbons with Water and Seawater, Part I: Hydrocarbons C5 to C7 (Pergamon, New York, 1989).