Reactive oxygen species generation in FeOCl nanosheets activated peroxymonosulfate system: Radicals and non-radical pathways

Chaoqun Tan; Qinglong Xu; Tianyu Sheng; Xinxin Cui; Zhiren Wu; Haiying Gao; He Li

doi:10.1016/j.jhazmat.2020.123084

Reactive oxygen species generation in FeOCl nanosheets activated peroxymonosulfate system: Radicals and non-radical pathways

J Hazard Mater. 2020 Nov 5:398:123084. doi: 10.1016/j.jhazmat.2020.123084. Epub 2020 Jun 4.

Authors

Chaoqun Tan¹, Qinglong Xu², Tianyu Sheng², Xinxin Cui², Zhiren Wu³, Haiying Gao¹, He Li¹

Affiliations

¹ School of Civil Engineering, Southeast University, Nanjing, 210096, China; Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education, Southeast University, Nanjing, 210096, China.
² School of Civil Engineering, Southeast University, Nanjing, 210096, China.
³ School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China.

PMID: 32768838
DOI: 10.1016/j.jhazmat.2020.123084

Abstract

Iron oxychloride (FeOCl) is utilized as a activator of peroxymonosulfate (PMS) for the degradation of paracetamol (APAP) and phenacetin (PNCT) in response to the water pollution by persistent pharmaceuticals. The degradation process was well fitted with a pseudo-first order kinetic pattern, and the excellent catalytic performance towards APAP (100 % removal) and PNCT (86.5 % removal) was obtained in the presence of 0.2 g/L FeOCl and 2.0 mM PMS at pH 7.0 in 30 min. In-situ electron spin resonance (ESR) and scavenging tests revealed the generation of a series of ROS (·OH, SO₄^-, O₂^-, ¹O₂), which was highly dependent on pH. Besides, the non-radical pathways process involved ¹O₂ was dominant in APAP oxidation, while both ·OH and ¹O₂ are significant in PNCT removal. Furthermore, the formation of disinfection by-products (DBPs) during post-chlorination showed neglectable increment at neutral and alkaline condition with FeOCl/PMS pre-oxidation, and the calculated cytotoxicity would experience a continuous deterioration with pH increase. These results displayed high efficiency of FeOCl/PMS system in micropollutants degradation and a relatively comprehensive activation process of PMS, which may promote practical application in environmental remediation.

Keywords: Disinfection by-products; Iron oxychloride; Peroxymonosulfate; Radical identification; Singlet oxygen.

Publication types

Research Support, Non-U.S. Gov't