Efficient decontamination of organic pollutants under high salinity conditions by a nonradical peroxymonosulfate activation system.
Water Res
; 191: 116799, 2021 Mar 01.
Article
em En
| MEDLINE
| ID: mdl-33453457
ABSTRACT
Peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) for wastewater treatment have recently attracted widespread interests. However, the degradation of organic pollutants via traditional radical-dominated pathway is severely limited by the side reactions between radicals and the co-existing inorganic anions, especially under high salinity conditions. Herein, an efficient Fe/O co-doped g-C3N4nanosheet catalyst was synthesized to dominantly activate PMS through a dual non-radical pathway with the singlet oxygen and high-valent iron-oxo species (Fe(V)=O). The rapid degradation of model pollutant bisphenol A (BPA) was achieved by dosing PMS (1 mM), catalyst (0.1 g/L) in a simulated high-salt wastewater (≥200 mM) of the developed Fe/O-doped g-C3N4+PMS system with a reaction rate constant of 1204-fold higher than that in g-C3N4+PMS system. The O and Fe co-dopants could reconfigurate the electronic structure of pristine g-C3N4 to produce more non-radical active species. The formed Fe(V)=O played a main role in the BPA degradation by promoting electron transfer from BPA molecule to the "metastable PMS/catalyst complex", which was verified by electrochemical tests and density functional theory calculations. The auxiliary transient productions of ·OH+SO4·- species were also favorable for the pollutant degradation. Excellent reusability in a wide pH range confirmed the practical application prospects of the Fe/O-doped g-C3N4+PMS system. The successive addition of PMS with a low dosage into the system rich in pollutants was confirmed to favor the PMS utilization. Our work unveils the potential applications of a non-radical dominated process for the decontamination of organic pollutants in saline water.
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01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poluentes Ambientais
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article