Small concentrations, big results: μM addition of photoactive iron oxides with PMS, PDS, or H₂O₂, leads to enhanced removal of viruses at near-neutral pH

abstract

The photo-Fenton process is effective for pathogen removal, and its low-cost versions can be applied in resource-poor contexts. Herein, a photo-Fenton-like system was proposed using low concentrations of iron oxides (hematite and magnetite) and persulfates (peroxymonosulfate - PMS, and peroxydisulfate - PDS), which exhibited excellent inactivation performance towards MS2 bacteriophages. In the presence of bacteria, MS2 inactivation was inhibited in H2O2 and PDS systems but promoted in PMS-involved systems. The inactivation efficacy of all the proposed systems for mixed bacteria and viruses was greater than that of the sole bacteria, showing potential practical applications. The inactivation performance of humic acid-incorporated iron oxides mediating photo-Fenton-like processes was also studied; except for the PMS-involved system, the inactivation efficacy of the H2O2- and PDS-involved systems was inhibited, but the PDS-involved system was still acceptable (< 2 h). Reactive species exploration experiments indicated that OH was the main radical in the H2O2 and PDS systems, whereas O-1(2) played a key role in the PMS-involved system. In summary, hematite- and magnetite-mediated persulfate-assisted photo-Fenton-like systems at low concentrations can be used as alternatives to the photo-Fenton process for virus inactivation in sunny areas, providing more possibilities for point-of-use drinking water treatment in developing countries.

keywords

SOLAR WATER DISINFECTION; NATURAL ORGANIC-MATTER; PHOTO-FENTON PROCESS; MEDIATED INACTIVATION; HYDROGEN-PEROXIDE; DECONTAMINATION; KINETICS; SUNLIGHT; UV

subject category

Engineering; Environmental Sciences & Ecology; Water Resources

authors

Jia, JL; Minella, M; Ruiz, MC; Decker, J; Li, D; Gonçalves, NPF; Prevot, AB; Lin, T; Giannakis, S

Groups

G1 - Porous Materials and Nanosystems

Projects

Nano-argilas para remoção/captura de fosfatos (P) e sua reutilização como fertilizante (NATURAL)

3D Printed Fouling-Resistant Photoactive Membranes for Wastewater Treatment (PURAQUA)

acknowledgements

This work was supported by funds from the National Key P & D Program of China (2022YFC3203702) , the Science and Technology Development Plans of the Ministry of Housing and Urban -Rural Development (2021-K-131) , and the Six Talent Peaks Project in Jiangsu Province (JNHB-004) . China Scholarship Council (202006120369) , Jiangsu Funding Program for Excellent Postdoctoral Talent (2023ZB646) , and the Hohai University full-time postdoctoral research fund (2016-423278) . National Natural Science Foundation of China for Youth (22306101) . Stefanos Giannakis would like to acknowledge the REDDIS project, 'Procesos reductivos como el Talon de Aquiles bacteriano en la desinfeccion de aguas residuales y en aguas naturales', which received funding from the Agencia Estatal de Investigacion (Spain) , 'Proyectos Consolidacion Investigadora 2022 ' (CNS2022-135728) , as well as the DETRAS Project, 'Desinfeccion-Descontaminacion de Efluentes Contra la Transmision de la Resistencia en Antibioticos' (APOYO-JOVENES-21-UXUKHL-88-WQWWQF) , funded by the Comunidad de Madrid through the call 'Research Grants for Young Investigators from Universidad Politecnica de Madrid'. Nuno Goncalves acknowledges funding from the European Union's Horizon Europe Research and Innovation Programme under the Marie Sklodowska-Curie Actions PF grant agreement No 101065059. Marco Minella and Alessandra Bianco Prevot acknowledge support from the Project CH4.0 under the MUR program 'Dipartimenti di Eccellenza 2023-2027 ' (CUP: D13C22003520001) .