(Liquid + liquid) equilibrium for the system (hydrolyzed palm oil + ethanol + water) for diacylglycerol enrichment

This work reports experimental results and the thermodynamic modelling of the (liquid + liquid) equilibrium of hydrolyzed palm oil (which contains triacylglycerols, diacylglycerols, monoacylglycerols and free fatty acids in its composition) with water and ethanol. The LLE values were obtained with the aim of enriching the palm oil diacylglycerol content by LLE extraction. The LLE experimental data were used to estimate UNIQUAC and NRTL parameters, which were used for (liquid + liquid) calculations employing the Gibbs free energy minimization approach. Experimental data were well correlated using UNIQUAC and NRTL models, in which the maximum value of root mean square deviation maximum of 0.75 wt.% was obtained. From the results obtained in this study, it was possible to demonstrate the feasibility of the palm oil diacylglycerol enrichment through liquid–liquid phase separation following the esterification procedure.

► We measured LLE for the system (hydrolyzed palm oil + ethanol + water).
► The experimental data were well correlated with UNIQUAC and NRTL models.
► Gibbs free energy minimization was used.
► Hydrolyzed palm oil can be diacylglycerol-enriched from a LL extraction process.