Cobalt(II) and nickel(II) transfer through charged polysulfonated cation exchange membranes

The transport of Co(II) and Ni(II) ions through charged polysulfonated ion exchange membranes under Donnan dialysis conditions has been studied as a f unction of pH gradient at 25 degreesC. In the Donnan dialysis process, the membrane is bounded by two electrolyte solutions, the one side (donor phase ) initially containing metal salts and the other H2SO4 with no external pot ential held applied. The transport of metal ions through membranes was corr elated with the flux data as well as with estimated diffusion coefficients and was found to depend on the interaction between the fixed groups in the membrane and the metal ions. It was observed that the pH gradient influence s the transport of metals and the flux of ions increases with H ion concent ration in the receiver phase. (C) 2000 Academic Press.