Preparation of Iron Oxalate from Iron Ore and Its Application in Photocatalytic Rhodamine B Degradation

Abstract

In this study, iron oxalate dihydrate (FOD-ore) was produced from iron ore by the process using oxalic acid to extract iron, followed by photo-reduction. Several techniques, such as X-ray powder diffraction (XRD), Raman, scanning electron microscopy with energy dispersive X-Ray analysis (SEM-EDX), ultraviolet–visible diffuse reflectance spectroscopy (UV-DRS), photoluminescence spectroscopy (PL), and X-ray photoelectron spectroscopy (XPS), were used to determine the physicochemical properties of the FOD-ore sample. To compare the photocatalytic activity of FOD-ore, commercial hematite (Fe2O3) was used as a precursor to creating iron oxalate (FOD). The FOD-ore was applied to the photocatalytic degradation of rhodamine B (RhB), a model organic pollutant in wastewater. Using the produced FOD-ore, we were able to degrade more than 85% of RhB within 90 min at a rate approximately 1.4 times higher than that with FOD. FOD-ore demonstrated greater light absorption than FOD, resulting in improved RhB degradation performance. Moreover, the enhanced separation and transport of photogenerated electron-hole pairs can be attributed to the increased photocatalytic RhB degradation rate of FOD-ore, confirmed by photoluminescence results. Therefore, FOD-ore can be utilized as a potential photocatalyst in the degradation process for other organic pollutants under light irradiation.