ALGINATE POLYELECTROLYTE IONOTROPIC GELS .3. KINETICS OF EXCHANGE OF CHELATED DIVALENT TRANSITION-METAL IONS ESPECIALLY COBALT(II) AND COPPER(II) BY HYDROGEN-IONS IN CAPILLARY IONOTROPIC METAL ALGINATE POLYMEMBRANE GELS

The kinetics and mechanism of exchange of cross-linked Cu2+ and Co2+ by H+ ions in their alginate gel complexes have been investigated, conductimetrically. The rate of exchange was found to decrease in the order Co > Ni > Cu alginates. The factors affected the rate of exchange such as the ionic radii of metal ions, width of capillaries, strength of chelation and the orientation of the solvent molecules and the macromolecular chains toward the chelated metal ions were discussed. The thermodynamic parameters of exchange have been evaluated and interpreted in terms of gel stability.