Nanoscale zero-valent iron for remediation of toxicants and wastewater treatment

Water pollution with heavy metals, organic dyes, microorganisms, pesticides, pharmaceuticals, fertilizers, and other pollutants has a significant negative impact on the ecosystem and drinking water quality, irreparably harming all living things. The advancement of nanotechnology realizes metal nanoparticles for the treatment and removal of toxic contaminants from wastewater using a variety of mechanisms. Due to its high surface area, high reactivity, and energy, nanoscale zero-valent iron (nZVI) is used as a novel nanocatalyst for environmental treatment and remediation. Metals, surfactants, nanometals, polymers, and other materials are used to modify the nZVI surface to increase its stability and prevent it from agglomeration and oxidation in water. Until recently, studies showed that nZVI exhibited promising applications for water treatment and remediation. The present review aims to provide the latest development of the chemically or biologically synthesized surface-modified nZVI for wastewater treatment. The potential application of the nZVI for the photocatalytic degradation, reduction, or adsorption of organic contaminants, heavy metals, nitrate, phosphate, and microbial disinfection from wastewater is reviewed. The contaminant’s removal mechanisms, the coating materials role, and operational conditions are discussed. Finally, future outlooks and perspectives are highlighted. © 2023 Informa UK Limited, trading as Taylor & Francis Group.