Singlet oxygen-dominated electrocatalytic oxidation treatment for the high-salinity quaternary ammonium compound wastewater with Ti/(RuxIry)O2 anode

Yong Cheng; Han-Qing Zhao; Aqiang Ding; Fei Chen; Jun Liu; Dazhi Fang; Chenglong Li; Yongkui Huang; Peili Lu

doi:10.1016/j.envres.2022.112815

Singlet oxygen-dominated electrocatalytic oxidation treatment for the high-salinity quaternary ammonium compound wastewater with Ti/(Ru_xIr_y)O₂ anode

Environ Res. 2022 Jun:209:112815. doi: 10.1016/j.envres.2022.112815. Epub 2022 Jan 29.

Authors

Yong Cheng¹, Han-Qing Zhao², Aqiang Ding¹, Fei Chen³, Jun Liu¹, Dazhi Fang⁴, Chenglong Li⁴, Yongkui Huang⁵, Peili Lu⁶

Affiliations

¹ State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of Three Gorges Reservoir Region 's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China.
² State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of Three Gorges Reservoir Region 's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China. Electronic address: hqzhao@cqu.edu.cn.
³ Key Laboratory of Three Gorges Reservoir Region 's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China.
⁴ Sinopec Chongqing Shale Gas Co., Ltd, Chongqing, 408400, China.
⁵ National and Local Joint Engineering Research Center of Shale Gas Exploration and Development, Key Laboratory of Shale Gas Exploration, Ministry of Natural Resources, Chongqing Institute of Geology and Mineral Resources, Chongqing, 401120, China.
⁶ State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China; Key Laboratory of Three Gorges Reservoir Region 's Eco-environment, Ministry of Education, Chongqing University, Chongqing, 400045, China. Electronic address: lupl@cqu.edu.cn.

PMID: 35093311
DOI: 10.1016/j.envres.2022.112815

Abstract

The widespread application of quaternary ammonium compounds (QAC) has posed a serious hazard to the environment and human being, and high concentration of Cl^- in QAC wastewater may further increase the difficulty of pollutants elimination. In this study, such a QAC wastewater under high salinity conditions was chosen as the target, the prepared Ti/(Ru_xIr_y)O₂ anode exhibited favorable catalytic performance for the oxidation and mineralization of QAC under high salinity conditions. Increasing the Ru/Ir ratio of Ti-based electrode coating also slightly promoted the inner catalytic capacity. The combination of electron paramagnetic resonance (EPR) and quenching experiments indicates that ¹O₂ served as a main reactive specie in the Ti/(Ru_xIr_y)O₂ electrooxidation system. The increase of pH could decrease the removal efficiency of QAC for the reduced ¹O₂ yield, and the rise of Cl^- concentration could favor the QAC oxidation, and Cl^- was a better electrolyte to promote the oxidation of organic contaminants when compared to Na₂SO₄ or Na₂CO₃. Additionally, the conversion pathway of the model pollutant was tentatively investigated, the results demonstrated that there were almost no halogenated final products residual by electrocatalytic oxidation with Ti/(Ru_xIr_y)O₂ anode. This study not only elucidate the reaction mechanism of Ti/(Ru_xIr_y)O₂ anode electrocatalytic oxidation of high salinity QAC wastewater, but also may provide an efficacious and eco-friendly method for the treatment of high salinity QAC wastewater.

Keywords: Electrocatalytic oxidation; High salinity; Quaternary ammonium compounds; Singlet oxygen; Ti/(Ru(x)Ir(y))O(2) anode.

Publication types

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

MeSH terms

Electrodes
Humans
Oxidation-Reduction
Quaternary Ammonium Compounds
Salinity
Singlet Oxygen
Titanium / chemistry
Wastewater* / chemistry
Water Pollutants, Chemical* / analysis

Substances

Quaternary Ammonium Compounds
Waste Water
Water Pollutants, Chemical
Singlet Oxygen
Titanium