Recent advances in applications of low-cost adsorbents for the removal of heavy metals from water: A critical review

The heavy metals mobilization in the environment due to the industrial revolution is of great concern because of the noxiousness of these metal pollutants and their adverse impacts on environment, humans and other living organisms. Therefore, the elimination of such contaminants from wastewater is necessary to safeguard the envrionment and human health. Bio-sorbents have gained considerable attention in recent times as low-cost sustainable materials for applications in water treatment. This review critically evaluates the modern developments in applications of bio-sorbents in water purification with an emphasis on adsorption. The heavy metals adsorption onto different bio-waste derived adsorbents is described in detail by elaborating the adsorption mechanism and their regeneration abilities. Finally, major challenges, hurdles, and opportunities are discussed, and a roadmap is suggested along with future research recommendations to ensure the effective applications of bio-sorbents in water purification systems.