Abstract
High-valent iron-oxo complexes show promise as green oxidants for water remediation but suffer from critical limitations in stability and pH adaptability. Herein, we report a facile method to synthesize amorphous SiO2-stabilized high-valent iron-oxo complexes via Na+ diffusion activation of iron/silicon-rich copper smelting slag. In the complex, the synergistic coexistence of two distinct silica‑oxygen tetrahedral configurations-basic Na2SiO3 and acidic SiO2 oxides establishes a self-regulating pH buffering system that stabilizes solution neutrality. This unique structural design ensures sustained oxidative activity of the complex, representing a significant advancement over conventional silica-supported catalysts due to its intrinsic acid-base regulatory capability. Thus, the deactivations of the oxidants including the proton-induced self-decomposition and the hydrolysis of iron by hydroxyl groups can be efficiently inhibited, thereby expanding the pH applicability (3–11). High-valent iron species can be continuously regenerated during peroxymonosulfate (PMS)-triggered reactions for the selective and efficient oxidation degradation of tetracycline hydrochloride (TC, 98.01% in 15 min) via non-radical pathway. Through methyl phenyl sulfoxide-directed oxidation, electron spin resonance, Mössbauer spectroscopy, and density functional theory calculations, the stabilizing mechanism of silicon was elucidated, confirming that the high valent iron-oxo act as the dominant active species. This work advances both hazardous waste valorization and high valent iron-oxo complex engineering, offering a robust solution for organic pollutant removal in complex aquatic environments.
Recommended Citation
C. Yan et al., "Amorphous SiO2-stabilized High-valent Iron-oxo Complexes Derived from Fe- and Si-rich Solid Wastes for Efficient Tetracycline Hydrochloride Degradation," Chemical Engineering Journal, vol. 519, article no. 165020, Elsevier, Sep 2025.
The definitive version is available at https://doi.org/10.1016/j.cej.2025.165020
Department(s)
Civil, Architectural and Environmental Engineering
Publication Status
Full Text Access
Keywords and Phrases
Amorphous SiO2; Copper smelting slag; High valent iron-oxo complexes; Nonradical pathway; Tetracycline hydrochloride
International Standard Serial Number (ISSN)
1385-8947
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2025 Elsevier, All rights reserved.
Publication Date
01 Sep 2025
Comments
National Natural Science Foundation of China, Grant 22466024