Role of nanoparticles in the treatment of industrial wastewater

Fresh, clean water is the most significant element on the planet for sustaining life. Due to the constantly increasing numbers of people and industries, increases in water demands are observed in all sectors, including domestic, agricultural, and industrial. However, the main problem is not about increases in demand, but rather our ways of using or exploiting the water available to us naturally. In the race toward more development and industrialization, we have developed an evil in the form of wastewater that contains large numbers of pollutants, such as dyes, heavy metals, organic compounds and bioorganisms, bio-inorganic compounds, and many others. These pollutants are dangerous and have severe effects on our ecosystem. As a consequence, ∼663 million people worldwide don’t have access to fresh, clean water. It is a sad note that, with about 70% of the composition of the earth as water, we are not able to provide clean drinking water to each and every living organism. However, in the last few decades, researchers/scientists have begun to focus on the removal of such pollutants from wastewater. In the last two decades, nanotechnologies/nanoparticles have been widely used in industrial wastewater treatment. Nanoparticles or nanoadsorbents have strong affinity to adsorb various substances due to their small size, which leads to a large surface area and large surface-to-volume ratio, larger active surface area, high porosity, and high reactivity. Among the various types and classes of nanomaterials, metal/metal oxides, carbonaceous nanomaterials, and noble metal nanoparticles are the most commonly used in this field. Therefore in this chapter we focus our attention on the role of these nanomaterials in industrial wastewater treatment. The mechanisms of contaminant removal are also discussed, to provide a clear overview of their suitability. The chapter also focuses on the role of these nanomaterials in recent technologies that have been tried/developed and aimed at purification/treatment of wastewater. © 2023 Elsevier Inc. All rights reserved.