Chapter 19 - Nanocomposite membranes for heavy metal removal

Abstract

Water pollution is one of the global challenges, which needs to be addressed urgently. The presence of heavy metals in wastewater possesses a serious threat to the environment and human health. The conventional techniques used for heavy metals removal from wastewater offer some limitations such as fouling, chemical requirement, and also, sludge formation, which require additional costs of disposal. Membrane technology offers advantages over conventional processes, and it overcomes the limitations offered by them. Nanocomposite membranes are a class of membrane processes, which involves incorporation of nanoparticles in the membrane, thus enhancing hydrophilicity, water flux, porosity, mechanical strength, swelling, and fouling resistance. Phase inversion method and interfacial polymerization are the common techniques used for the preparation of nanocomposite membranes. Various nanocomposite membranes used for removal of heavy metals such as chromium, cadmium, arsenic, copper, nickel, and lead are discussed in this chapter. The comparison of nanocomposite membrane processes with conventional processes for heavy metal removal is also reviewed. Although there are reports of excellent performance of nanocomposite membranes at bench-scale level, they possess some challenges for application at industrial level, which are discussed.