Nanoclays as Eco-friendly Adsorbents of Arsenic for Water Purification

Abstract

The presence of arsenic (As) in water intended for human consumption and wastewater represents a high level of dangerousness for both human health and the environment. Partial or complete removal of this metalloid from water is an important objective for environmental remediation in many parts of the world. Generally, As is present as As(III) and As(V) in water; the As(III) species is more harmful to humans. The use of original and modified nanoclays is a promising new technology for elimination of all traces of As by adsorption. Nanoclays display important characteristics that make them a viable methodological alternative for adsorption of polluting metals. They are abundant in nature and inexpensive, have high biocompatibility, and can be reused. Strategic functionalization of nanoclays allows optimization of the process of absorption of some polluting metals because modifications of the original clays allow control of their composition and change several parameters – such as the surface area, interlaminar space and volume, and porosity – that are responsible for the adsorption and desorption properties of the clays. This aim of this chapter is to review current developments in the use of original and functionalized nanoclays for removal of As by adsorption processes. The outlook and future prospects for this methodology are also discussed.