Assessment of Cationic Salts and Inorganic Acids as Washing Agents for Cs-137 Removal from Radioactively Contaminated Electric Arc Furnace Dust

T his work investigated the effectiveness of cationic salts combined with inorganic acids as washing agents for removing Cs-137 from electric arc furnace dust (EAFD). To evaluate their performance, various cationic salts, specifically BaCl2, KCl, and NH4Cl, were studied at concentrations ranging from 0.5 to 2.0 M. Results demonstrated that removal efficiency using BaCl2 remained constant at 80%, while KCl and NH4Cl yielded 90.19%, and 90.11%, respectively. H2SO4 and HNO3 were selected as the inorganic acids. Effective combinations of 2.0 M KCl and 2.0 M NH4Cl cationic salts paired with 1.0 M H2SO4 and 1.0 M HNO3 were examined to determine their synergistic effects on enhancing Cs-137 extraction from contaminated EAFD. All experiments were conducted using a ratio of 1:2 contaminated EAFD to solvent. The combination of 2.0 M NH4Cl and 1.0 M H2SO4 demonstrated the most promising results, achieving Cs-137 removal efficiency of 96.09%. The structural characteristics of EAFD contamination, both pre- and post-treatment, were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX).