Electrochemical characterization of ion-exchange resin beds and removal of cobalt by electrodeionization for high purity water production

The characterization of three cation exchange resins, IRN77, SKN1, and IR120, for the removal of cobalt ions from an aqueous solution by electrodeionization (EDI) was studied. The study includes investigation of resin. beds in terms of their ion exchange capacity, electrical conductivity, and zeta potential. The conductivity of a resin bed was analyzed using a porous-plug model to understand the current path. From the experiments, more than a 97% cobalt ion removal was achieved under optimal conditions. Furthermore, production of ultrapure water with a two-stage EDI process was tested for the reuse of treated water.