DETERMINATION OF KINETICS AND DIFFUSION-COEFFICIENTS OF METAL SORPTION ON CA-ALGINATE BEADS

Efficiency of Ca-alginate beads in the removal of Ba2+, Cd2+, UO22+ and Zn2+ from aqueous solutions was evaluated. Effects of process variables (initial metal ion and calcium alginate concentrations, pH and temperature) on the kinetics of the biosorption process were assessed. The maximum rate of metal sorption, v(m), and the corresponding diffusion coefficient, D(M2+), were derived to be: [GRAPHICS] The apparent activation energy was derived from the Arrhenius plot to be 11.3 kJ/mol. This relatively low value of activation energy suggests that the biosorption process is diffusion controlled.