Publication Details |
| Category | Text Publication |
| Reference Category | Journals |
| DOI | 10.1016/j.watres.2025.123633 |
Licence  |
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| Title (Primary) | Multi-element isotope fractionation analysis to investigate the photosensitized reactions of humic substance with 3-chloroaniline |
| Author | Min, N.; Yao, J.; Li, H.; Kümmel, S.
; Schaefer, T.; Hermann, H.; Richnow, H.H. |
| Source Titel | Water Research |
| Year | 2025 |
| Department | TECH |
| Volume | 282 |
| Page From | art. 123633 |
| Language | englisch |
| Topic | T7 Bioeconomy |
| Supplements | https://ars.els-cdn.com/content/image/1-s2.0-S0043135425005433-mmc1.docx |
| Keywords | Humic substances; Photosensitization; Multi-isotope fractionation; Chloroanilines; Radical reactions; Photodegradation |
| Abstract | Dissolved organic matter including humic-like substances (HS), acting as photosensitizers participating in electron transfer reactions, can generate a variety of reactive species, such as OH radicals and excited triplet state HS (3HS*) and related, which promote the degradation of organic contaminants such as 3-chloroaniline (3-CA). Multi-element-compound-specific stable isotope analysis (ME-CSIA) was applied to characterize photosensitized mechanisms employing 3-CA as a probe. HS were irradiated with artificial sunlight for elucidation of the reaction mechanisms by studying the kinetic isotope effect (2H, 13C, 15N and 37Cl) to characterize the first irreversible bond change reaction. Unique enrichment factors (-1.0±0.3 for 13C, 7.4±1.7 for 2H and 2.3±0.7 for 37Cl) have been detected in HS/UV experiments (OH radical and triplet state), which indicate complex reaction mechanisms. Triplet state reference experiments with the artificial photosensitizers 4,5,6,7-tetrachloro-2′,4′,5′,7′-tetraiodofluorescein in the presence O2 (Rose Bengal-O2) or absence of O2 (Rose Bengal-O2 free) yielded characteristic enrichment factors (-0.3±0.2‰ and -1.2±0.2‰ for 13C, 2.7±0.5‰ and 4.8±1.0‰ for 15N and 8.4±3.3‰ and 11.2±6.8‰ for 37Cl), allowing interpretation of reaction mechanisms of triplet state with 3-CA. The correlation of 2H vs 13C, 15N vs 13C and 37N vs 13C fractions could be used diagnostically to determine photosensitized reactions in the environment and to differentiate between biodegradation, hydrolysis and photosensitized HS reaction. |
| Persistent UFZ Identifier | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=30745 |
| Min, N., Yao, J., Li, H., Kümmel, S., Schaefer, T., Hermann, H., Richnow, H.H. (2025): Multi-element isotope fractionation analysis to investigate the photosensitized reactions of humic substance with 3-chloroaniline Water Res. 282 , art. 123633 10.1016/j.watres.2025.123633 |
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