Enhanced oxidation and in-situ coagulation Fe(Ⅱ)/peroxymonosulfate-Mn(Ⅶ) process for carbamazepine removal: Multiple promoting effects of Mn and direct/indirect regulation of Cl- on active substances transformation

Yanli Kong; Siyu Dai; Qingwu Chen; Yong Nie; Jiangya Ma

doi:10.1016/j.jhazmat.2024.136933

Enhanced oxidation and in-situ coagulation Fe(Ⅱ)/peroxymonosulfate-Mn(Ⅶ) process for carbamazepine removal: Multiple promoting effects of Mn and direct/indirect regulation of Cl- on active substances transformation

J Hazard Mater. 2024 Dec 18:485:136933. doi: 10.1016/j.jhazmat.2024.136933. Online ahead of print.

Authors

Yanli Kong¹, Siyu Dai², Qingwu Chen², Yong Nie¹, Jiangya Ma³

Affiliations

¹ School of Civil Engineering and Architecture, Anhui University of Technology, Maanshan, Anhui 243002, China; Engineering Research Center of Biomembrane Water Purification and Utilization Technology, Ministry of Education, Maanshan, Anhui 243002, China.
² School of Civil Engineering and Architecture, Anhui University of Technology, Maanshan, Anhui 243002, China.
³ School of Civil Engineering and Architecture, Anhui University of Technology, Maanshan, Anhui 243002, China; Engineering Research Center of Biomembrane Water Purification and Utilization Technology, Ministry of Education, Maanshan, Anhui 243002, China. Electronic address: majiang_ya@ahut.edu.cn.

PMID: 39708606
DOI: 10.1016/j.jhazmat.2024.136933

Abstract

Slow transformation efficiency of Fe(III)/Fe(II) limits the generation of radicals in peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs), and these radicals was easy to be interfered by the presence of water constituents. In addition, in-situ coagulation during this oxidation process was neglected. This study proposed Fe(II)/PMS-Mn(VII) in the presence of chlorides ions (FPMC) process to reveal multiple promoting effects of Mn on redox cycle of Fe(III)/Fe(II) and different reactive mechanisms of Cl^- on types of radicals generation pathways, and the in-situ coagulation enhanced mechanisms was investigated. Results showed that the dual functionality of oxidation and in-situ coagulation in FPMC process was significantly enhanced that carbamazepine (CBZ) could be efficiently and quickly removed. The reduction product Mn(III) of Mn(VII) could promote the redox cycle of Mn(II)/Mn(III) and Mn(III)/Mn(IV) that facilitated Fe(III)/Fe(II), sustaining the reactivity of the system. Cl^- could significantly promote the cycling of Mn(Ⅲ)/Mn(Ⅳ) that indirectly affected the cycle of Fe(III)/Fe(II).

Keywords: Chlorides ions; Enhanced oxidation; In-situ coagulation; Peroxymonosulfate; Redox cycle.