The occurrence of pharmaceutical contaminants in wastewater poses an obstacle to aquatic ecosystems and human health. Naproxen (NPX), a carboxylate-based and piroxicam (PIR), a non-carboxylate-based drug, are utilized non-steroidal anti-inflammatory drugs (NSAIDs) commonly found in wastewater. Therefore, the advancement of effective approaches for removing such pollutants is critical. In this study, a novel photocatalyst, magnetic FeAl2O4-modified activated carbon (MAC-WS II), derived from walnut shell (WS), was fabricated for NPX and PIR removal. MAC-WSII demonstrated remarkable efficiencies of 99.15 and 98.49% for NPX and PIR after 45min, respectively, attributed to synergistic mechanism, integrating adsorption, photocatalysis and photo-Fenton process, which facilitated rapid charge transfer and effective electron-hole separation, as confirmed by electrochemical characterization.The kinetics of the synergistic reaction represented enhancements of 8.80 and 2.16- fold for PIR, and 13.39 and 2.33-fold for NPX, compared to adsorption alone and photocatalysis with adsorption, respectively. Furthermore, the rate constants of MAC-WS II were 2.74 times higher for PIR and 6.66 times higher for NPX compared to AC-WS II, indicating the important role of iron active centers in enhancing photocatalytic performance. Superoxide (•O2−) and hydroxyl (•OH) radicals were key species in photocatalysis and photo-Fenton reactions with varying contributions. Additionally, MAC-WS II retained 90.1 and 87.07% removal efficiency for PIR and NPX, respectively after five cycles, with negligible Fe and Al leaching after seven days of immersion in different solutions, confirming its outstanding stability. These findings establish MAC-WS II as an effective and sustainable photocatalyst for the remediation of pharmaceutical contaminants in wastewater.

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