Removal of Chromium Ions Using Radiation Graft Polymerization

The discharge of heavy metals, particularly chromium (Cr), driven by industrialization has raised serious environmental concerns. In this study, hollow-fiber ultrafiltration membranes were modified using radiation-grafting polymerization to fabricate functional ion-exchange membranes for chromium ion removal. Glycidyl methacrylate was first grafted onto the membrane surface, followed by the introduction of diethylamine, monoethanolamine, and sodium sulfite to produce anion- and cation-exchange membranes. Adsorption performance under various conditions was evaluated through batch experiments, and reusability was assessed via desorption tests. The anion-exchange membrane exhibited effective Cr (VI) adsorption under acidic conditions, achieving a desorption efficiency of approximately 95%. The cation-exchange membrane exhibited high Cr (III) adsorption capacity at pH 4 and a desorption efficiency of approximately 80%. The findings suggest that ion-exchange membranes fabricated via radiation-graft polymerization can be effectively applied for the removal of Cr ions.