Liquid–liquid equilibrium data for ternary systems of water + lactic acid + C4–C7 alcohols at 298.2 K and atmospheric pressure

• Lactic acid solubilizes preferably in the studied solvents than in water.
• Immiscibility region increases in the order: 2-butanol < 1-butanol < 1-pentanol < 1-hexanol < 1-heptanol.
• 1-Pentanol shows better performance for lactic acid removal than others C4–C7 alcohols.
• NRTL correlates well the data, except for 2-butanol.
• Detailed uncertainty propagation was calculated.

Liquid–liquid equilibrium data for water + lactic acid + {1-butanol or 2-butanol, 1-pentanol, 1-hexanol, 1-heptanol} systems at T = 298.2 K and atmospheric pressure (≈95 kPa) were determined by density and refractive index measurements. The systems present Treybal's type I binodal curves. Obtained tie line data were correlated with NRTL model. Cloud points, tie lines, partition coefficients, selectivities and percent of extraction indicate that 1-pentanol is better than the other solvents studied for lactic acid removal from water.