Chitosan-based modalities with multifunctional attributes for adsorptive mitigation of hazardous metal contaminants from wastewater

Abstract

The increase in population and industrialization has intensified water scarcity and stress, and contaminated water bodies. Therefore, the development of advanced water and wastewater treatment technologies has gained global attention from researchers. Adsorption, using natural materials (nano, polymer, and bio) is one of the most cost-effective, less challenging, and well-known technologies for wastewater treatment and improving water quality. Among them, chitosan (CS) has demonstrated a set of unique features, such as biodegradability, eco-friendliness, availability, low cost, and biocompatibility. Hence, this review provides an overview of some recent advancements in the removal of heavy metals, including As (III) and (V), Cd (II), Cu (II), Cr (VI), and Pb (II) by CS-based adsorbents, and their potential effects on human health. It also covers the synthesis of CS-based adsorbents for the elimination of mentioned contaminants in recently reported studies. In addition, this study recommends encountering potential drawbacks by enhancing the adsorption capacity by incorporating functional groups, nanoparticles, and other materials. These modifications may help increase selectivity for specific metal contaminants and synthesize adsorbents that can perform better over a wide range of pH. Insights gained from this study will guide researchers in the future toward optimal water treatment and pollutant elimination strategies.