Chiang Mai Journal of Science

     This 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).