Solubility and tie line data of the water–phosphoric acid–solvents at T = 303.2, 313.2, and 323.2 K: An experimental and correlational study

Experimental solubility and tie-line data for (water + phosphoric acid + 1-decanol or 1-dodecanol or 1-dodecanethiol) ternary systems were obtained at T = 303.2, 313.2, and 323.2 K and atmospheric pressure for the first time. The investigated systems display two types of LLE behavior. The systems consisting of the heavy alcohols exhibit type-1 LLE behavior, while, a type-2 behavior is exhibited by the other system. Cloud point method was used to obtain the solubility data and the Karl-Fischer, acidimetric titration, and refractive index methods were used to determine the tie-line data. The Othmer–Tobias and Hand correlations equations were used to ascertain the quality of the LLE data. Distribution coefficients and separation factors were determined to evaluate the extracting capability of the solvents. The experimental LLE data were regressed and adequately correlated with the UNIQUAC and NRTL models.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Liquid–liquid equilibrium data of (water + phosphoric acid + solvents) systems were measured. ► Experimental LLE data were correlated with NRTL and UNIQUAC models. ► Distribution coefficients and separation factors were evaluated.