THE SYNTHESIS AND CHARACTERIZATION OF MODIFIED PERIWINKLE SHELL FOR HEAVY METAL REMOVAL

The synthesis and modification of periwinkle shell ash (PSA) using choline chloride–glycerol (ChCl–Gly) deep eutectic solvent (DES) proved to be an effective, sustainable, and eco-friendly approach. The DES treatment enhanced the removal of organic impurities, improved surface area, and promoted the formation of reactive sites on the shell material. After calcination, the modified PSA exhibited improved structural and chemical properties such as higher calcium oxide content, better porosity, and stronger adsorption or catalytic potential. These findings demonstrate that ChCl–Gly DES can serve as a green alternative to conventional chemical treatments, offering a low-cost route to produce value-added materials from waste periwinkle shells while minimizing environmental impact.