Reactive solvent extraction processes have shown superiority in the separation of dissolved molecules (either inorganics, organics or bioproducts) from aqueous solutions. These processes offer many advantages, such as faster mass transfer rate, higher selectivity and less operational constraints, compared to the conventional processes. Hollow-fiber contactors have demonstrated great success in large-scale applications for the extraction/recovery of dissolved “target” components (inorganic and organic molecules) from aqueous samples. In this process the compound is preferentially extracted, from the aqueous source solution, to an organic solvent (either pure or in liquid membrane form - a mixture solvent and a specific extractant) through the walls of porous fibres of the membrane contactor. Then the extracted solutes are recovered from the organic solution to another solution, on the shell side of the contactor. The overall mass transfer of the process is an important parameter that provides guidelines in designing such a process at industrial scale. The value of the overall mass transfer coefficient can be calculated using correlation and the operating conditions of the experiment. In this report, a simplified solution is presented, using the physical data of the contactor (the volume to mass transfer area ratio), the experimental data of concentration-time, and the operating parameters in the hollow-fibre contactor. The experimental data for recovery of aroma compounds from synthetic aqueous solution using n-hexane and sunflower oil (literature data) are analysed using this solution. The values of the overall mass transfer coefficient determined from the simplified equation are comparable to those obtained from mass transfer correlations in the literature. The predictions of this approximate solution are very close to the experimental results and very well comparable with the numerical solution of the complete model.