Rice bran oil extraction with CO2-expanded acetone: kinetics modeling, and thermodynamics aspects

• CO 2 -expanded acetone extraction and process modeling were investigated. • CO 2 -expanded acetone diffusion depends on temperature and particle size. • The modified Fick’s model expressed extraction kinetics data with high precision. • CO 2 addition to acetone reduced the activation energy by 68 % and enhanced extraction. • The rice bran oil extraction process was endothermic, irreversible, and spontaneous. Mathematical modeling for process control, simulation, optimization, and equipment design is necessary to gain technological insights. This study compares kinetic models and emphasizes thermodynamic aspects of rice bran oil extraction with CO 2 -expanded acetone. Analysis of extraction kinetic data shows that the modified Fick’s model is superior to Peleg’s model. A thermodynamic study demonstrates that adding CO 2 to acetone lowers the activation energy by 68 %. Moreover, the enthalpy, entropy, and Gibbs free energy changes for CO 2 -expanded acetone extraction at 5.0 MPa, 25 °C, and a CO 2 mole fraction of 0.76 are determined to be 141.10 KJ/mol, 9.80 J/mol, and –2.90 KJ/mol, respectively, indicating that the rice bran oil extraction process is endothermic, irreversible, and spontaneous. These findings enhance the design and scale-up of efficient bio-oil extraction processes using CO 2 -expanded acetone.