OpenFoam modelling of microchannel liquid-liquid extraction of ternary mixture of isooctane + thiophene + two methylimidazolium dicyanamide-based ionic liquids

• Liquid-liquid extraction of a ternary mixture was successfully performed in a microchannel system, achieving over 96% of equilibrium values. • [emim][DCA] used to separate thiophene from iso-octane at 313.15 K and atmospheric pressure. • The extraction process was simulated using the interMixingFOAM module in OpenFOAM, validating results against experimental data. • The method shows strong potential for hydrocarbon stream purification and desulfurization in industrial processes through optimized CFD-driven design. Liquid-liquid extraction in a microchannel system was investigated for a ternary mixture of iso-octane, thiophene, and two ionic liquids: 1-ethyl-3-methylimidazolium dicyanamide [emim][DCA] and 1-butyl-3-methylimidazolium dicyanamide [bmim][DCA] at 313.15 K and atmospheric pressure. The microchannel approach was selected to enhance mass transfer and separation efficiency due to its large interfacial area and short diffusion distances. The extraction process was analyzed using a computational method and the results were validated against experimental data. Simulations were conducted using interMixingFOAM module available in OpenFOAM, a widely recognized open-source computational fluid dynamics (CFD) software, to model the flow dynamics and mass transfer behavior within the microchannel. The simulations validated the reliability of OpenFOAM in modeling and optimizing LLE processes, achieving > 96% of the equilibrium values of the mole fractions of the extracted components obtained for 100 microns channel width. The study demonstrated the effectiveness of OpenFOAM in predicting the behavior of liquid-liquid extraction in microchannels, providing detailed insights into phase distribution and concentration gradients. The results confirmed the high efficiency of this method for separating thiophene from iso-octane using [emim][DCA] and [bmim][DCA] as effective solvents. This approach holds significant promise for industrial applications in the purification of hydrocarbon streams, particularly in desulfurization processes, by using the accuracy of CFD simulations to optimize performance of liquid-liquid extraction processes.