Abstract
Iron ions contribute to soil acidification and loss of availability of phosphorus when the iron wastewater is applied to cropland. In this study, nonthermal dielectric barrier plasma discharge treatment is engineered to remove and recover iron from wastewater. The impact of three individual process parameters, i.e., AC applied voltage of 4–8 kV, frequency of 10–20 kHz, and pH of 2.2–3.6 in the wastewater, as well as their interactive effects on iron removal, were evaluated and modeled using response surface methodology (RSM). The maximum iron removal efficiency of 99 % was obtained within 10 min when applied voltage, frequency, and pH were set at 8 kV, 20 kHz, and 3.6, respectively, for which the energy efficiency (EE) was determined to be 560 g/kWh. The recovered particles from iron removal were characterized with X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS) and determined to be Fe2O3 particles with 5–20 μm size, showing the potential to be used as a catalyst.