Sustainable Microwave-Assisted Extraction of Zn, Fe, and Cs from Electric Arc Furnace Dust

Steel production generates a byproduct called electric arc furnace dust (EAFD), which contains metals such as zinc (Zn) and iron (Fe), as well as cesium-137 (137Cs), a hazardous radionuclide. The presence of 137Cs-contaminated EAFD is a result of the accident and has adverse effects on the environment and human health. Therefore, the separation of 137Cs, Zn, and Fe is essential step for managing radioactive waste. This work studied the effect of microwave-assisted extraction on the simultaneous removal of radionuclides and metals from EAFD, in comparison with the conventional method. Moreover, leaching experiments were performed using H2SO4 and KOH under controlled conditions, with microwave irradiation applied at 450 W for 30 min. The physical properties of raw EAFD were studied by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, which were consistent with our previous work. Microwave-assisted extraction showed superior performance compared to the conventional method, achieving approximately 80% removal of 137Cs with H2SO4 in a single 30-min cycle. Moreover, the release of Fe (3,913.85 ± 3.86 mg/kg) and Zn (45,162.22 ± 4.78 mg/kg) was significantly higher under the same conditions. The microwave-assisted extraction process enables rapid and uniform heating, reducing both energy consumption and acid usage compared with conventional leaching methods. This approach provides a simple, low-cost, and energy-efficient method for treating hazardous EAFD. It allows effective management of radioactive waste and the recovery of major metals from EAFD for potential future use.