Liquid–liquid equilibria for ternary system water + toluene + benzaldehyde at (303.2–343.2) K

•LLE data for water + benzaldehyde + toluene were measured.•The LLE data were measured at (303.2–343.2) K and atmospheric pressure.•Reliability of the LLE data were checked by both Othmer–Tobias and Hand equation.•UNIQUAC and NRTL model was used to correlate the experimental LLE data.

Liquid–liquid equilibrium (LLE) data for the ternary system of water + benzaldehyde + toluene have been determined at (303.2–343.2) K under atmospheric pressure. The Othmer–Tobias and the Hand correlations were used to check the reliability of the experimental data. The obtained LLE data were correlated by both the NRTL and UNIQUAC activity coefficient models. The relevant interaction parameters were extracted by the regression of the experimental data. The calculated values by these two models show good consistency with the measured data. The relative-mean-standard deviations obtained is 0.82% by the NRTL model and 0.12% by the UNIQUAC model. The obtained interaction parameters might be used in the calculation of LLE for the ternary system water + benzaldehyde + toluene as well as for the design and optimization of the related separation process.