Prospects of iron oxide nanomaterial for remediation of wastewater

Industrialization, urbanization, and economic development emit hazardous wastes and other toxicants into the environment, thereby negatively impacting the biosphere. Exploitation of water resources at an alarming rate has caused a severe water crisis across the planet, imposing a potential threat to mankind. It has been estimated that approximately 3.5 billion people will suffer due to lack of available potable water by 2025. Groundwater and surface water account for 30% of available fresh water and are being exploited by domestic, industrial, and agricultural sectors. Approximately 80% of the available fresh water is inaccessible due to spatial, geological, and climatic factors. Furthermore, anthropogenic activities have led to the contamination of 18% of the available freshwater, leaving only 2% of fresh water for consumption. Industrial discharge into water bodies is the leading contributor of water pollution. Conservative (heavy metals, persistent organic pollutants) and complex organic and inorganic compounds are characteristic contaminants present in various industrial discharges. Various treatment methods (physical, chemical, and biological) are being employed for the treatment of industrial wastewater, but these methods require huge financial investment and consume large amounts of energy. Nanotechnology has emerged as the most promising and innovative solution for the remediation of water pollutants. Researchers have explored the potential of nanomaterials for the adsorption of heavy metals and the removal of other potential water contaminants. This chapter provides a brief overview on the application of iron oxide-based nanomaterials in remediation of various industrial discharges. It also highlights the synthesis and characterization of iron oxide-based nanomaterials and their relative feasibility for sustainable environmental applications.