Extraction of microalgae oil by organic solvents: experimental determination and modeling of liquid–liquid equilibria using vegetable oils mixture as a model system

Abstract

This work presents liquid–liquid equilibrium data for systems formed of organic solvents (acetone and dimethyl sulfoxide) and a vegetable oil blend composed of palm and coconut oils (MOPC). The MOPC represents the crude oil of the microalgae Chlorella pyrenoidosa as a basis for studying the liquid–liquid extraction in the oil refining stage. The equilibrium data for the MOPC + dimethyl sulfoxide + acetone systems were determined at four temperatures (293.15, 298.15, 308.15, and 318.15 K). Experimental binodal curves were performed by the cloud point determination, showing a decrease of the biphasic region with temperature increment. The UNIQUAC model was used to correlate the experimental data, using tripalmitin triacylglycerol properties to represent the vegetable oil blend. The standard deviation between the experimental and calculated data was 1.33%. The quality of experimental data and regressed parameters were checked by analyzing the Gibbs energy of the mixing function’s topology.