The system nitromethane + 1-nonanol + water includes a three-phase region. All three binary pairs of components, nitromethane + 1-nonanol, nitromethane + water and 1-nonanol + water, are partially miscible. The data for first two systems were compiled and critically evaluated (Sazonov et al.³). The UCST (upper critical solution temperature) of the binary system nitromethane + 1-nonanol has been reported in Sazonov and Chernysheva² as 327.96 K and to agree with recommended value in Sazonov et al.³ The 1-nonanol + water system been critically evaluated in Barton.⁴
     The solubility temperatures of the three and two liquid phases portions of the ternary system were determined by the synthetic method in ternary mixtures with constant mass relationship of (1) and (2), Sazonov and Chernysheva.¹ Experimental errors were not reported, but are estimated by the evaluator to be ± 0.1 K (temperature) and ± 0.002 mass fractions (solubility). Depending on temperature the system nitromethane + 1-nonanol + water forms a miscibility gaps of Type I to III, Treybal.⁵ In the temperature range 273 K to 328 K, where three binary systems are partially miscible, the solubility curves correspond to Type III (Treybal⁵). A three-phase region occurs below 318.3 K (Sazonov and Chernysheva¹). Maximal temperature of the three-phase liquid equilibrium was reported to be 318.3 K (Sazonov and Chernysheva¹). Two separate regions of immiscibility exist above 318.3 K, one of these is described by band type curves. In the temperature range 328 K to 376.3 K (UCST of binary nitromethane + water system), where two binary systems nitromethane + water and 1-nonanol + water are partially miscible, the solubility curves correspond to Type II (Treybal⁵). Above 376.3 K this ternary system has only one partially miscible region, Sazonov and Chernysheva.¹

     Compositions of coexisting two and three liquid phase regions of the ternary system nitromethane + 1-nonanol + water were determined at 293.15 K, 296.15 K and 318.25 K by gas chromatography (Sazonov and Chernysheva²) and presented in Fig. 17 . Experimental errors were not reported, but are estimated by the evaluator to be ± 0.002 mass fractions (composition).
     All experimental data are considered tentative.

Experimental Data:   (Notes on the Nomenclature)