Experimental Measurement and Modeling of Liquid–Liquid Equilibria for the Ternary System Water + Propan-1-ol + Ethyl Acetate

Abstract

The world’s growing energy needs and the depletion of fossil fuels have driven demand for renewable alternatives, such as biofuels. Propan-1-ol is a valuable biofuel component; however, the presence of water during its production remains a significant challenge. A viable solution is liquid–liquid extraction to selectively recover propan-1-ol from a water mixture. Ethyl acetate is considered a promising solvent due to its chemical stability, eco-friendly nature, moderate water immiscibility, and favorable density difference for phase separation in a water-propan-1-ol mixture. In this study, ternary LLE measurements for water (1), propan-1-ol (2), and ethyl acetate (3) were conducted at 298.15, 313.15, and 328.15 K to evaluate ethyl acetate as a solvent for extracting propan-1-ol. The selectivity and capacity of the solvent were calculated. The experimental data were modeled using the NRTL and UNIQUAC activity models, both of which adequately describe the phase behavior, with NRTL slightly better than UNIQUAC. The group method of data handling (GMDH) neural network was also employed to complement the thermodynamic model, accurately predicting phase composition. The findings of this study show that ethyl acetate has excellent potential for selectively extracting propan-1-ol from water, with the extraction efficiency increasing with temperature.