Validation of quenching effectiveness and pollutant degradation ability of singlet oxygen through model reaction system

Limiao Cai; Qian Yao; Xiaodong Du; Jiayi Zhong; Haijian Lu; Xueqin Tao; Jiangmin Zhou; Zhi Dang; Guining Lu

doi:10.1016/j.jhazmat.2023.132488

Validation of quenching effectiveness and pollutant degradation ability of singlet oxygen through model reaction system

J Hazard Mater. 2023 Oct 15:460:132488. doi: 10.1016/j.jhazmat.2023.132488. Epub 2023 Sep 7.

Authors

Limiao Cai¹, Qian Yao², Xiaodong Du¹, Jiayi Zhong³, Haijian Lu², Xueqin Tao³, Jiangmin Zhou⁴, Zhi Dang⁵, Guining Lu⁶

Affiliations

¹ School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
² Guangdong Provincial Academy of Environmental Science, Guangzhou 510045, China.
³ College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China.
⁴ College of Life and Environmental Science, Wenzhou University, Wenzhou 325035, China.
⁵ School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou 510006, China.
⁶ School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, China. Electronic address: lutao@scut.edu.cn.

PMID: 37696208
DOI: 10.1016/j.jhazmat.2023.132488

Abstract

Quenching method is widely used to assess the contribution of specified reactive species through the probe inhibition efficiency (IE) caused by adding excessive quencher. However, for reactive species with weak ability such as singlet oxygen (¹O₂), the quenching results are prone to ambiguity. In this study, an ¹O₂ system using furfuryl alcohol (FFA) as a probe was successfully constructed by methylene-blue-N vis-photosensitization, to discuss the quenching, interference elimination and pollutant degradation ability of ¹O₂. Inhibition of FFA transformation caused by both quenching and interrupting of ¹O₂ production was found. The quenching is affected by quencher dosage and ability, which depends on the second-order-rate constant (k). A high k means a strong ability, and less dosage is required to achieve the same IE. Comparison between the calculated ratio of reactive species consumed by quencher and experimental IE helps to judge the interruption of ¹O₂ production. None of the organic-solvents (methanol, ethanol, iso-propanol, n-butanol, iso-butanol, tert-butanol, tetrahydrofuran, acetonitrile, acetone and chloroform) scavenged ¹O₂, which would be used as screening-agent for other reactive species (e.g., hydroxyl radicals) that would interrupt ¹O₂ contribution assessment. Besides, ¹O₂ was powerless to degrade most selected pollutants. These results encourage proper use of quenchers and better experimental design.

Keywords: Furfuryl alcohol; Photosensitization; Quenching; Singlet oxygen; Triplet state.