Clay minerals and clay-based materials for heavy metals pollution control

Heavy metal contamination is a huge hazard to the environment and human health, and research into removing heavy metals from their primary sources (industrial and agricultural wastes) has increased significantly. Adsorption has received interest due to its distinct benefits over other treatment approaches. The distinctive qualities of clay minerals, such as their high specific surface area, strong cation exchange capacity, and varied structures, make them particularly ideal for use in the manufacture of adsorbents. The customizable structure and performance of clay minerals allow for unprecedented diversity in adsorbent creation, opening up new possibilities for the development of high-efficiency and functional adsorption technologies. In this review, various approaches for developing optimal adsorbents from raw materials are presented. Then, the correlation between functionalization and performance is investigated, focusing on the effects of structural features and surface properties on adsorption performance. The research progress on the synthesis of adsorbents using clay minerals and other functional materials is systematically reported. Finally, the challenges and opportunities in designing and utilizing innovative clay mineral adsorbents are discussed.