Iron Oxide Nanomaterials for Water Purification

Abstract

There is a growing worldwide concern for the development of wastewater treatment technologies. Industrial and domestic waste water are generated from anthropogenic activities, which are a threat to the environment and require remediation to overcome environmental damage, and thus reduce risks to human. Nanotechnology provides the ability to manipulate materials at the nanoscale with desirable properties. A wide variety of environmental clean-up technologies have been used in wastewater treatment, including applying iron oxide nanomaterials as nano sorbents for removal of pollutants from water. Iron oxide nanoparticles can be used as a coagulant to remove contaminants from water. Iron oxide nanoparticles have been studied due to their many advantages compared with other materials. The application of iron oxide nanomaterials has received much attention due to their exceptional properties, such as extremely small size, high surface area to volume ratio, surface modifiability, magnetic properties and great biocompatibility. Iron oxides consist of anion arrangements, usually hexagonal or cubic, in which the vacuoles are partially filled with divalent or trivalent iron, with predominantly octahedral (FeO6) and tetrahedral (i.e., Fe3O4) coordination arrangements observed. This chapter provides an overview of the preparation and characterization of iron-based nanoparticles (NPs), such as zerovalent iron nanoparticles from plant extracts that have been prepared for the efficient removal of a wide range of pollutants. The iron oxide nanoparticles are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, differential/thermogravimetric analysis, N2 adsorption–desorption, BET surface area, and Fourier-transform infrared spectroscopy. The advancements and future perspectives of iron-based nanoparticles, the applications of iron oxide nanomaterials in wastewater treatment, and the drawbacks that limit their large-scale field application are highlighted.