Details

Autor(en) / Beteiligte

• Xu, Jiaxin
• Zou, Jing
• Wu, Jianying
• Zeng, Huiping
• Huang, Yixin
• Yang, Jingxin
• Gong, Chunming
• Chen, Siying
• Ma, Jun

Titel

Enhanced chlorination of diclofenac using ABTS as electron shuttle: Performance, mechanism and applicability

Ist Teil von

• The Science of the total environment, 2024-01, Vol.907, p.168117-168117, Article 168117

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2024

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Chlorination, one of the most common oxidation strategies, performed limited degradation capacity towards many emerging organic contaminants under neutral pH conditions. In this study, 2,2′-azinobis(3-ethylbenzothiazoline)-6-sulfonate (ABTS) was discovered to possess an outstanding activation property towards free available chlorine (FAC) during the chlorination of diclofenac (DCF) among pH 6.0–9.5. ABTS radical (ABTS+) primarily accounted for the elimination of DCF in the ABTS/FAC system, although hydroxyl radicals, reactive chlorine species, and singlet oxygen were also generated via the self-decomposition of FAC. ABTS acted as the electron shuttle to degrade DCF in the ABTS/FAC system, where ABTS was firstly oxidized by FAC to ABTS+ via single electron transfer, and followed by the elimination of DCF with the generated ABTS+. Eight DCF degradation intermediates were identified by LC/Q-TOF/MS, and four DCF degradation pathways were proposed. Real water bodies, humic acid, and the coexistent anions of Cl−, HCO3−, NO3−, and SO42− performed negligible influence on DCF removal in ABTS/FAC system. ABTS/FAC system was much superior to sole chlorination in terms of toxicity reduction and anti-interference capacity. Overall, this study innovatively introduced ABTS as the electron shuttle to enhance the oxidative capacity of FAC under neutral pH conditions and provided a new insight that the ABTS-like organic/synthetic components might play an important role in degrading emerging organic contaminants by chlorination in water treatment. [Display omitted] •ABTS significantly enhanced the chlorination of diclofenac under neutral pH conditions.•ABTS+ made the primary contribution on diclofenac elimination in ABTS/FAC system.•ABTS acted as the electron shuttle to enhance diclofenac removal in ABTS/FAC system.•The ABTS/FAC system was superior to sole chlorination in terms of toxicity reduction.•The ABTS/FAC system had better anti-interference capacity compared to sole chlorination.