Insight into the mechanisms of trichloronitromethane formation by vacuum ultraviolet: QSAR model and FTICR-MS analysis  

作　　者：Xiaojun Chen Yangtao Wu Weiqiu Zhang Lingjun Bu Shumin Zhu Da Sheng Shiqing Zhou John C.Crittenden 

机构地区：[1]Key Laboratory of Building Safety and Energy Efficiency,Ministry of Education,Department of Water Engineering and Science,College of Civil Engineering,Hunan University,Changsha 410082,China [2]School of Civil and Environmental Engineering and the Brook Byers Institute for Sustainable Systems,Georgia Institute of Technology,Georgia 30332,USA

出　　处：《Journal of Environmental Sciences》2023年第3期215-222,共8页环境科学学报（英文版）

基　　金：supported by Natural Science Foundation of Hunan Province (No. 2021JJ40066);National Natural Science Foundation (Nos. 51878257 and 52100007).

摘　　要：Vacuum ultraviolet(VUV) photolysis is recognized as an environmental-friendly treatment process. Nitrate(NO-3) and natural organic matter(NOM) are widely present in water source.We investigated trichloronitromethane(TCNM) formation during chlorination after VUV photolysis, because TCNM is an unregulated highly toxic disinfection byproduct. In this study:(1) we found reactive nitrogen species that is generated under VUV photolysis of NO-3react with organic matter to form nitrogen-containing compounds and subsequently form TCNM during chlorination;(2) we found the mere presence of 0.1 mmol/L NO-3can result in the formation of up to 63.96 μg/L TCNM;(3) we found the changes in pH(6.0-8.0), chloride(1-4 mmol/L), and bicarbonate(1-4 mmol/L) cannot effectively diminish TCNM formation;and,(4) we established the quantitative structure-activity relationship(QSAR) model,which indicated a linear relationship between TCNM formation and the Hammett constant(σ) of model compounds;and,(5) we characterized TCNM precursors in water matrix after VUV photolysis and found 1161 much more nitrogen-containing compounds with higher aromaticity were generated. Overall, this study indicates more attention should be paid to reducing the formation risk of TCNM when applying VUV photolysis process at scale.

关 键 词：Vacuum ultraviolet Natural organic matter Hammett constant FTICR-MS Trichloronitromethane 

分 类 号：X703[环境科学与工程—环境工程]