Liquid-liquid equilibria provide basic data and guidance regarding the design, simulation, and development of an appropriate solvent extraction process. In the current work, the data for the liquid-liquid equilibrium (LLE) of water + cyclohexanone + isophorone and water + cyclohexanone + mesityl oxide systems have been measured at temperatures of 308.15-328.15 K and pressure of 101.3 kPa. The empirical Bachman and Hand equations were utilized to confirm the consistency of experimentally determined LLE data. Meanwhile, the solute distribution ratio and separation parameter were obtained from the experimental equilibrium data to evaluate the extraction properties of the selected solvents. Additionally, a mathematical regression of experimental tie-line compositions for all of the investigated ternary mixtures was performed by means of the nonrandom two-liquid and universal quasi-chemical activity coefficient models to acquire corresponding optimized binary interaction parameters. The correlation results were verified to be coincident with the experimental ones and revealed that the above two thermodynamic models were of high-accuracy and suitable to regress the tie-line compositions for the investigated ternary systems.