In the presence of surface-active reagents, the flux of mass transfer into/from the droplets drastically decreases within the liquid-liquid extraction units. Therefore, particular design equations are required to incorporate the presence of contaminants in the design of industrial-scale extraction columns: In the combinatorial model of Slater, the mass-transfer coefficients for the continuous and dispersed phases are corrected with the aid of a contamination factor. However, since the latter factor in the Slater model is originally obtained from the experimental data, the Slater model is unable to predict the behavior of an extraction system where the experimental data are not available. In this research, the model of Slater, i.e., single-drop single-solvent model, was employed to simulate the experimental data of a water-acetone-toluene system in the presence of three surface-active reagents, i.e., SDS, Triton X-100, and DTMAC. These components exhibit anionic, cationic, and nonionic surfactants, respectively. The experimental data provided by Saien et al. for both directions of the mass transfer, i.e., continuous to dispersed phases and vice versa, were employed. Based on the experimental data along with the theoretical principles, an empirical model for the contamination factor was developed. The provided model predicts the mass-transfer coefficients within 4% of certainty only through the physical properties data of the phases, independent of the surfactant type. Two different mechanisms for the mass transfer within the liquid droplets, depending on the size of the droplets, have been recognized. Simulation of the extraction system by the aid of the present model, along with the combinatorial model of Slater and the terminal velocity model of Grace, predicts the experimental results satisfactorily.