Nanoparticle Innovations in Wastewater Treatment: A Comparative Study of Titanium Dioxide, Gold, and Nano Zero-Valent Iron Nanoparticles for Lead, Chromium, and Mercury Removal
Nanoparticles have emerged as a potent solution for addressing the complexities of wastewater treatment due to their unique physicochemical properties, including high surface area, reactivity, and potential for surface functionalization. This review explores the effectiveness of titanium dioxide (TiO2), gold nanoparticles (Au NPs), and nano zero-valent iron (nZVI) in the removal of heavy metals and organic pollutants. Each nanoparticle type offers distinct advantages: TiO2 for its photocatalytic activity and stability, Au NPs for their high selectivity and biocompatibility, and nZVI for its strong reductive properties and cost-effectiveness. However, the deployment of these nanoparticles also raises significant environmental and health concerns, including potential toxicity to aquatic life, long-term persistence, unintended release, and the risks associated with bioavailability and mobility. Additionally, human health risks, particularly from occupational exposure, underscore the need for careful handling and comprehensive risk assessments. Real-world applications demonstrate their utility in various contexts, from industrial effluent treatment and municipal wastewater management to emergency response and portable water systems. The review underscores the importance of ongoing research to develop safer and more sustainable nanomaterials, along with the establishment of regulatory frameworks to mitigate potential risks.
Keywords: Nanoparticles, Wastewater treatment, Heavy metal removal, Environmental risks, Photocatalysis
