KINETIC-ANALYSIS OF COUPLED TRANSPORT OF THIOCYANATE IONS THROUGH LIQUID MEMBRANES AT DIFFERENT TEMPERATURES

Non-steady-state kinetics of coupled transport of thiocyanate ions thr ough liquid membrane (trichloromethane), containing hexadecyl trimethy l ammonium chloride as a carrier, was examined at different temperatur es. The kinetics of thiocyanate transport could be analyzed in the for malism of two, consecutive, irreversible first order reactions. The in fluence of temperature on the kinetic parameters (k(ld), k(2m), R-m(ma x), t(max), J(d)(max), J(a)(max)) have been also investigated. The mem brane entrance rate, k(ld), and the membrane exit rates, k(2m) and k(2 a), increase with temperature. For maximum membrane entrance and exit fluxes, J(d)(max) and J(a)(max), the activation energies were found fr om the slopes of the two linear relationships: 7.75 and 8.30 kcal/mol, respectively. The values of the found activation energy indicate that the process is controlled by species difussion.