Industrial & Engineering Chemistry Research, Vol.49, No.12, 5808-5815, 2010
Stability and Performance Study of Water-in-Oil-in-Water Emulsion: Extraction of Aromatic Amines
One of the major obstacles to the application of emulsion liquid membranes to industrial separations is the stability of emulsion globules. Stability of emulsion is affected by two phenomena globule rupture and osmotic swell. Interfacial shear between the continuous and membrane phase causes the liquid membrane to thin and, in some cases, rupture, thereby affecting separation. Destabilization phenomena affecting the homogeneity of dispersions are emulsion globule migration (creaming, sedimentation) and size variation or aggregation (coalescence, flocculation). In the present study, the stability of an emulsion liquid membrane is studied by varying different parameters, for example, internal acid phase and surfactant concentration and stirrer speed for emulsification. Dispersion destabilization of the emulsion is detected by Turbiscan. Properties such as interfacial tension, drop size distribution, photomicrographs, and zeta potential are also analyzed to evaluate emulsion stability. A stable emulsion is used for the removal of aromatic amines from aqueous solutions. An advancing reaction front model considering competitive transport of aromatic amines has been proposed to simulate data. The simulated curves are found to be in good agreement with the experimental data.