Kinetic and mechanistic insights into the photo-Fenton oxidation of polystyrene nanoplastics in water

Microplastics and nanoplastics (NPs) are widespread in aquatic environments and readily accumulate along the food chain. Given their varied sizes in real systems, evaluating degradation processes at various scales is essential for a comprehensive understanding of their fate. In this study, the photo...

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Detalles Bibliográficos
Autores: Bedia García-Matamoros, Jorge, Luca, Carla di, Abarkan, Amiina, Cherta, Laura, Muñoz García, Macarena, Martínez de Pedro, Zahara, Casas de Pedro, José Antonio
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/743780
Acceso en línea:https://hdl.handle.net/10486/743780
https://dx.doi.org/10.1016/j.jwpe.2025.108838
Access Level:acceso abierto
Palabra clave:Photodegradation
Photo-Fenton
Nanoplastics
Advanced oxidation processes
Water treatment
Polystyrene
Química
Descripción
Sumario:Microplastics and nanoplastics (NPs) are widespread in aquatic environments and readily accumulate along the food chain. Given their varied sizes in real systems, evaluating degradation processes at various scales is essential for a comprehensive understanding of their fate. In this study, the photo-Fenton degradation of polystyrene (PS) nanospheres with initial particle sizes of D 0 = 140, 252, 460, 909, and 1100 nm was investigated. Oxidation evolution and treatment efficiency were assessed using turbidity and Total Organic Carbon (TOC) measurements, while Transmission Electron Microscopy (TEM) provides insights into particle size and morphological changes. Pyrolysis–Gas Chromatography/Mass Spectrometry (Py-GC/MS) and Ion Chromatography (IC) were used to identify intermediate degradation products. The results demonstrated that smaller particles degraded more rapidly due to their higher surface-to-volume ratio, with complete TOC removal achieved for all particle sizes in relatively short reaction times (40–80 min). The degradation kinetics were accurately described using the Shrinking Core Model and the Prout-Tompkins Model, which revealed distinct stages of reactivity and sigmoid behavior. During the initial activation phase, oxygenated surface groups were incorporated into the PS NPs, followed by chain scission and oxidation into low-molecular-weight aromatic and aliphatic compounds. Finally, these intermediates were fully mineralized into CO 2 residual NPs