Sustainable Synthesis of Zinc Oxide and Its Application in Water Contaminant Removal

This study explores the sustainable synthesis of zinc oxide (ZnO) from industrial waste and its application in removing water contaminants such as chloramphenicol (CAP), metronidazole (MNZ), and prometryn (PROM). ZnO synthesized from zinc production waste (ZnO(2)) exhibited competitive photocatalytic performance compared to commercial ZnO (ZnO(1)), achieving 79% CAP degradation (Kd = 0.53 × 10−2 min−1) and 72% MNZ degradation (Kd = 0.43 × 10−2 min−1) under UV light, while showing higher activity in PROM degradation (32% removal) due to its mesoporous structure. Although ZnO(2) had a slightly lower specific surface area (24.9 m2/g) and pore volume (0.26 cm3/g) than ZnO(1), it demonstrated significant environmental and economic benefits by repurposing industrial waste. Catalytic tests in ethanol oxidation revealed ZnO(2) required higher temperatures for full conversion but exhibited higher acetaldehyde selectivity (70%). These findings highlight the potential of waste-derived ZnO as a sustainable alternative for water treatment and catalytic processes, aligning with circular economy principles and reducing reliance on natural resources.