Characterization of Chemically Synthesized Nano-zerovalent-Iron (nZVI) Prepared for Removing Contaminants from Wastewater

Water pollution is a global issue, prompting increased efforts to eliminate pollutants from water sources. This study focuses on the preparation and characterization of chemically synthesized nanomaterials, specifically nano-zero-valent iron (nZVI), to be used as absorbents targeting Cd and Pb pollutants. nZVI analysis confirms the presence of predicted components in both irradiated and non-irradiated adsorbent materials. The created nZVI exhibits a 3D square crystallite structure with a crystallite size of 60.80 nm, as revealed by energy dispersive X-ray-equipped scanning electron microscope SEM-EDX. FTIR analysis attributes the significant absorption of Pb and Cd to the O-H stretch functional group vibrations of carboxylic groups. pH variations notably impact nZVI adsorption capacity and selectivity distribution, with the highest Pb and Cd removal observed at pH 3, followed by pH 4, while the lowest removal rate occurs at pH 8.5. Pb adsorption capacity correlates with pH trends, whereas Cd exhibits slight increases up to pH 6 then tended to decrease before decreasing at pH 7 and 8.5. Activity of irradiated or non-irradiated nZVI on removing Cd and Pb was influenced by contact time with the contaminants.The removal effectiveness of Pb remains consistent between irradiated and non-irradiated nZVI, and improved with extended contact time up to 180 min. Conversely, non-irradiated nZVI outperforms irradiated nZVI in Cd removal, with the highest removal efficiency achieved at 180 min. Overall, both irradiated and non-irradiated nZVI demonstrate optimal performance at 180 minutes, achieving producing the highest removal efficiency.