Nano-Adsorbents and Nano-Catalysts for Wastewater Treatment

Abstract

Purification of wastewater containing industrial effluents, heavy metals, and synthetic dyes attracted attention of the researchers. Different types of methods including adsorption, ion exchange and distillation were reported. Metal oxide (bi and tri-metallic) nanoparticles, silica nanoparticles, nanostructural graphene oxides, etc. were studied for their applications in wastewater treatments through various methods including adsorption process and catalytical degradation. Nanomaterials with small particle size, (1–100 nm), active surface area, pollutant binding capacity, catalytic potential, reusability, and stability are the better choice of materials for wastewater treatment. Demands of fresh and hygienic water are most important for life-sustaining, but due the anthropogenic activity industrial wastes like heavy metals, pesticides, synthetic dyes, and radioactive wastes pollute the water bodies. Researchers have applied different techniques to capture heavy metal ions, dye molecules and other harmful pollutants from water. From all these techniques the most acceptable and easy methods is the adsorption process which involves the adsorption of pollutants onto its surface. Moreover the catalytic degradation of bulkier synthetic dye molecules to small fraction of low toxicity is also a good way to treat textile water. A variety of nano-adsorbents and nano-catalysts including mono-, bi-, tri-metal, and metal oxides nanoparticles, and their functionalized forms have been studied so far. The current chapter provides the detailed overview of the variety of nano-adsorbents and catalysts and their applications for waste water treatment. Different techniques of material synthesis, characterization, material properties, adsorption and catalytic parameters are also illustrated.