CuFe2O4/diatomite actuates peroxymonosulfate activation process: Mechanism for active species transformation and pesticide degradation

Peng Xu; Rui Wei; Peng Wang; Xiang Li; Chunyan Yang; Tianyao Shen; Tong Zheng; Guangshan Zhang

doi:10.1016/j.watres.2023.119843

CuFe₂O₄/diatomite actuates peroxymonosulfate activation process: Mechanism for active species transformation and pesticide degradation

Water Res. 2023 May 15:235:119843. doi: 10.1016/j.watres.2023.119843. Epub 2023 Mar 13.

Authors

Peng Xu¹, Rui Wei¹, Peng Wang², Xiang Li¹, Chunyan Yang¹, Tianyao Shen¹, Tong Zheng³, Guangshan Zhang⁴

Affiliations

¹ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
² State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: pwang73@hit.edu.cn.
³ State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address: zhengtong@hit.edu.cn.
⁴ College of Resource and Environment, Qingdao Engineering Research Center for Rural Environment, Qingdao Agricultural University, Qingdao 266109, China. Electronic address: gszhang@qau.edu.cn.

PMID: 36934540
DOI: 10.1016/j.watres.2023.119843

Abstract

Peroxymonosulfate (PMS) activation is a promising technology for water purification, but the removal performance of multiple pollutant matrices and the mechanism for reactive species transformation in the heterogeneous catalytic system remain ambiguous. Herein, a novel CuFe₂O₄/diatomite was fabricated for PMS activation to achieve efficient removal of typical pesticides. Uniform distribution of CuFe₂O₄ on diatomite efficiently alleviated the agglomeration of CuFe₂O₄ and increased specific surface area (57.20 m² g^-¹, 3.8-fold larger than CuFe₂O₄). CuFe₂O₄/5% diatomite (5-CFD)/PMS system showed nearly 100% removal efficiency for mixed pesticide solution within 10 min (0.10 g L^-¹ 5-CFD and 0.40 g L^-¹ PMS) and excellent anti-interference performance towards various coexisting substances (≥90% removal efficiency). The electrochemical measurements confirmed that the lower charge transfer resistance of 5-CFD significantly enhanced the electron-transfer capacity between 5-CFD and PMS, accelerating the reactions among Fe(III)/Fe(II), Cu(II)/Cu(I), and PMS, further generating •OH (261.3 μM), ¹O₂ (138.8 μM), SO₄^•- (11.8 μM), and O₂^•-. The O in reactive oxygen species didn't originate from dissolved oxygen (DO) but PMS, independent of the low solubility of DO and slow diffusion rate of O₂ in water. Furthermore, the production of ¹O₂ went through the process: PMS → O₂^•- → ¹O₂, and SO₄^•- could rapidly convert into •OH. The degradation pathways and the evolution of intermediates were proposed by HPLC-QTOF-MS/MS and DFT calculations. QSAR analysis illustrated that the toxicity became lower with the reaction process. This study provides novel insights into the mechanism for pesticide degradation and active species transformation and the anti-interference capability of systems.

Keywords: Active species transformation; Anti-interference capability; CuFe(2)O(4)/diatomite; Degradation pathways; Peroxymonosulfate activation; Pesticides.

MeSH terms

Ferric Compounds*
Peroxides / chemistry
Tandem Mass Spectrometry
Water Pollutants, Chemical* / chemistry

Substances

peroxymonosulfate
diatomite
Ferric Compounds
Water Pollutants, Chemical
Peroxides