Radioactive iodine and chloride transport across a paper membrane bearing trimethylhydroxypropylammonium anion exchange groups

The separation performance of radioactive iodine from radioactive waste is examined using the paper membrane made of long length pulp fiber bearing trimethylhydroxypropylammonium anion exchange group. Prepared paper membrane is sturdy and high of ion-exchange capacity as the introduction of ion exchange group into the paper membrane with high density and well-bonding between pulp fibers are achieved. Ion transport across the paper membrane is evaluated with electroconductive membrane permeability derived from transmembrane potential and membrane conductance data, and diffusional membrane permeability derived from transmembrane potential and ionic flux in Na¹²⁵I or Na ³⁶Cl single electrolyte concentration-cell system. The ratio of electroconductive membrane permeability of ¹²⁵I to that of ³⁶Cl reaches 6.2, while the ratio of diffusional membrane permeability of ¹²⁵I to that of ³⁶Cl is almost unity. The novel prepared paper membrane exhibits the ¹²⁵I permselectivity by solution/membrane distribution process due to electrostatic effect.