Chapter 9 - Metal oxides and their nanocomposites in wastewater treatment

Abstract

The anthropogenic activities have resulted in the generation of wastewater from industries which is indiscriminately released into the environment and water bodies without treatment. The effluent from the industries contains contaminants such as toxic dyes, heavy metals, antibiotics, oils, and auxiliary chemicals. These pollutants are highly toxic to human beings and also destructive to aquatic life. Hence, there is a need for efficient treatment of industrial effluents before reuse or discharge into the environment. Different treatment techniques such as adsorption, reverse osmosis, coagulation, filtration, and others had been previously used, but adsorption remains the best due to its easy operation, flexibility, low maintenance cost, and high effectiveness. Several adsorbents had been used for the removal of contaminants from wastewater through the adsorption technique. In this chapter, metal oxides and their nanocomposites are explored for their effectiveness in wastewater treatment. Particularly, the green and chemical preparation techniques of the metal oxides and their nanocomposites are discussed, along with their characterization methods and properties. In this work, the adsorption mechanisms for the application of metal oxides and their nanocomposites in wastewater treatment are discussed. This chapter highlights the current knowledge on metal oxide and their nanocomposites for the effective adsorption of contaminants from wastewater.