Liquid–liquid equilibrium (LLE) data for the (water + phosphoric acid amyl acetate) ternary systems were determined at T = 298.2 K and p = 101.3 kPa. The cloud point method was used to obtain the solubility and the Karl-Fischer, acidimetric titration, and refractive index methods were used to determine the tie-line value. The ternary systems exhibit type-1 behavior of LLE through the Othmer-Tobias plot. Experimental distribution coefficients and separation factors were evaluated over the biphasic region. The experimental results show the ability of amyl acetate for the extraction of phosphoric acid from aqueous solutions. Experimental distribution coefficients and separation factors were fitted using the Kamlet–Taft LSER model.
