Hierarchical ultra microporous aluminum based metal organic aerogels for water purification: Kinetic, isotherm, and regeneration insights into diclofenac adsorption

The widespread use of Diclofenac (DCF), a non-steroidal anti-inflammatory drug (NSAID) has resulted their persistent presence in aquatic environments which posing risks to both human health and ecosystems. In this study, we synthesized aluminum-based metal organic aerogels (Al-MOAs) through a Sol-gel method to explore the efficiency as adsorbents for DCF removal is aqueous solution. Al-MOAs exhibited a high microporosity, high specific surface area (1702.5 m2/g), and excellent mechanical stability confirmed by physicochemical characterization. Therefore, Al-MOAs revealed fast adsorption kinetics and achieved a maximum adsorption capacity of 416 mg/g at pH 3. The adsorption process was found to be spontaneous and exothermic with multiple interactions, including electrostatic forces, hydrogen bonding, and π-π stacking, contributing to the high removal efficiency as well. Furthermore, Al-MOAs demonstrated suitable stability and exhibiting outstanding reusability for at least four consecutive adsorption-desorption cycles during DCF removal process. Finally, Al-MOAs considered as a promising adsorbent for the efficient removal of pharmaceutical pollutant in liquid phase and a sustainable solution for wastewater treatment.