2 - Applications of nanomaterials for adsorptive removal of various pollutants from water bodies

Abstract

The recent developments in nanotechnology that took place over the past decades have presented new opportunities for the removal of various pollutants from water sources. To date, there is a growing body of studies on different nanomaterials and their applications, especially in the context of water and wastewater treatment. This chapter discusses recent developments in the use of nanomaterials, including metal oxides, carbon-based nanomaterials, and dendric polymers, in the adsorptive removal of pollutants from water bodies. Because of their availability, stability, and cost-effectiveness, metal oxides have attracted most of the attention by both researchers and decision-makers. However, metal oxide nanoparticles tend to agglomerate to decrease their surface energy. So, one way to enhance their stability is to coat their surface with capping agents. Examples include polymers, surfactants, inorganic and organic modifiers, carbon-based, or natural products. The chapter also discusses the environmental parameters affecting the adsorption process, including the medium, pH, temperature, and the nature of the surface interaction between the species involved in the process, with more focus on comprehending the adsorption mechanism and kinetics. A discussion on recent advances on the use of carbon-based materials such as graphene and carbon nanotubes (CNT) is addressed as well. Finally, the chapter discusses the current status of nanomaterials and their implementation in either pilot- or full-scale applications. The challenges facing this implementation, including the potential toxicity and social concerns, are outlined.