KINETICS OF THE SEPARATION CONCENTRATION OF CHROMIUM(VI) WITH EMULSION LIQUID MEMBRANES

In this work the kinetics of the separation-concentration of Cr(VI) with emulsion liquid membranes is reported. After selection of the conditions where membrane breakage and water transport to the inner phase can be neglected, kinetic experiments were performed in a stirred tank contactor starting with Cr(VI) concentrations in the range 40-1000 mg/L and using the following composition of the liquid membrane: Aliquat 336, 0.5% V(m); decanol, 5% V(m); Paranox 106, 1.5% V(m); kerosene. The advancing front model correlates satisfactorily well the experimental data, an effective diffusion parameter, D(eff)/R2 = 3.26 X 10(-4) min-1, has been calculated, and the validity of this model has been checked from the comparison of the simulated curves using the calculated parameter and the experimental results.