Mechanochemical synthesis of multivariate UPO-3 (Cu-ZIF-9-ica) MOF for inactivation of antibiotic-resistant bacteria and irrigation-quality water production via heterogeneous photo-Fenton catalysis

Abstract

Water scarcity and pollution are critical global challenges, particularly in agriculture, the largest consumer of water. The development of sustainable, effective, and environmentally friendly disinfection methods is essential to address the risks posed by antibiotic-resistant bacteria and to ensure safe reuse of water for irrigation. In this study, we report the synthesis of the metal-organic framework (MOF) Universidad Pablo de Olavide-3 (UPO-3) via a mechanochemical approach, a scalable and sustainable method compared to traditional solvothermal synthesis. The resulting UPO-3/H₂O₂ system exhibits robust photocatalytic properties under visible light, achieving effective and broad-spectrum antibacterial activity. The disinfection efficiency of the catalyst was evaluated against Escherichia coli as a model of microbial pathogen in two saline matrices, considering the key parameters of the heterogeneous photo-Fenton process, including catalyst dosage, initial H₂O₂ concentration, and light irradiation. Notably, it inactivated two important virulent and antibiotic-resistant bacterial pathogens (Staphylococcus aureus and Pseudomonas aeruginosa). Furthermore, UPO-3 shows exceptional performance under real-world conditions, such as river water disinfection, achieving >5-log reduction of E. coli, fulfilling a critical criterion for Class A water reuse under Regulation (EU) 2020/741. These results highlight UPO-3 as a versatile and sustainable solution for water reuse, addressing water scarcity and advancing efforts to achieve United Nations Sustainable Development Goal 6.