Liquid-liquid equilibria of ternary aqueous mixtures containing alcohols and alkyl levulinates

Highlights: • LLE data were measured for the ternary aqueous mixtures containing alkanols and alkyl levulinates. • The studied alkanols are methanol, ethanol and n-butanol. • The studied alkyl levulinates are ethyl levulinate and n-butyl levulinate. • The LLE tie-line data were checked with Othmer-Tobias correlation. • The experimental LLE tie-line data well correlated with NRTL model. The liquid–liquid equilibrium (LLE) data were measured for the ternary systems of water + methanol + ethyl levulinate, water + ethanol + ethyl levulinate, and water + n-butanol + n-butyl levulinate in a temperature range of 298.15 K to 328.15 K and at 101.3 kPa. Among the investigated mixtures, the ethyl levulinate-containing systems are categorized as a type-I LLE and their areas of two-liquid-phase region decreases with increasing temperature. The ternary system of water + n-butanol + n-butyl levulinate behaves as a type-II LLE and interestingly its area of two-liquid-phase region increases with an increase of temperature over the experimental condition. These new LLE tie-lines data were correlated accurately with the NRTL model.