Simultaneous mitigation of disinfection by-product formation and odor compounds by peroxide/Fe(II)-based process: Combination of oxidation and coagulation

Xiaoyu Liu; Shunke Ding; Pin Wang; Yuntao Hong; Hongying Zhao; Wenhai Chu

doi:10.1016/j.watres.2021.117327

Simultaneous mitigation of disinfection by-product formation and odor compounds by peroxide/Fe(II)-based process: Combination of oxidation and coagulation

Water Res. 2021 Aug 1:201:117327. doi: 10.1016/j.watres.2021.117327. Epub 2021 Jun 4.

Authors

Xiaoyu Liu¹, Shunke Ding¹, Pin Wang¹, Yuntao Hong¹, Hongying Zhao², Wenhai Chu³

Affiliations

¹ State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Ministry of Education Key Laboratory of Yangtze River Water Environment, Tongji University, Shanghai, 200092, China; International Joint Research Center for Sustainable Urban Water System, Tongji University, Shanghai, 200092, China.
² School of Chemical Science and Engineering, Tongji University, Shanghai, 200092, China.
³ State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Ministry of Education Key Laboratory of Yangtze River Water Environment, Tongji University, Shanghai, 200092, China; International Joint Research Center for Sustainable Urban Water System, Tongji University, Shanghai, 200092, China. Electronic address: 1world1water@tongji.edu.cn.

PMID: 34144483
DOI: 10.1016/j.watres.2021.117327

Abstract

To remove disinfection by-product (DBP) precursors and mitigate odor compounds, peroxide (peroxymonosulfate and persulfate)/Fe(II)-based process was applied as a combination of coagulation and oxidation. Compared with traditional Fe-based salt coagulation (FeSO₄ and FeCl₃), peroxide/Fe(II)-based process was more efficient in dissolved organic carbon, UV₂₅₄ and turbidity removal, and peroxymonosulfate showed better performance than persulfate. The better coagulation performance arose from a combination of enhanced neutralization and different characteristics of flocs. Even though the combined process would increase the bromine substitution factor of DBPs, DBP formation and DBP-associated toxicity after peroxide/Fe(II)-based process were 9.2-38.8% and 5.2-27.2% lower than that after conventional Fe(III) coagulation. Both enhanced dissolved organic matter removal and oxidation of DBP precursors played vital roles in DBP control. Conventional Fe-based salt coagulation could hardly remove odor compounds (less than 10%, generally), whereas 28.2-84.9% of odor compounds were degraded during peroxide/Fe(II)-based process, due to free radical formation. This study demonstrated that PMS/Fe(II)-based process might be a promising treatment process for simultaneous DBP control and odor removal in source water.

Keywords: Disinfection byproducts; Enhanced coagulation; Fe(II)-based advanced oxidation processes; Taste and odor compounds.

MeSH terms

Disinfection
Ferric Compounds
Ferrous Compounds
Odorants
Peroxides
Water Pollutants, Chemical* / analysis
Water Purification*

Substances

Ferric Compounds
Ferrous Compounds
Peroxides
Water Pollutants, Chemical