Sustainable Removal of Dyes from Wastewater Using Eggshell-Derived Calcium Carbonate Nanoparticles: Adsorption Isotherms, Kinetics, and Thermodynamic Analysis Supporting Sustainable Development Goals (SDGs)

This study explores eggshell waste as a low-cost, eco-friendly adsorbent for removing Aniline Blue dye from water. Batch and continuous experiments under various conditions showed effective performance. FTIR and SEM analyses confirmed porosity and functional groups. The adsorption followed the Sips isotherm and pseudo-first-order kinetics. The porous calcium carbonate structure enhanced dye removal. Thermodynamic results indicated an endothermic and spontaneous process. Lower flow rates improved performance in fixed-bed columns. The study supporting environmentally friendly solutions aligned with the Sustainable Development Goals (SDGs).