Updated Reaction Pathway for Dichloramine Decomposition: Formation of Reactive Nitrogen Species and N-Nitrosodimethylamine
| العنوان: | Updated Reaction Pathway for Dichloramine Decomposition: Formation of Reactive Nitrogen Species and N-Nitrosodimethylamine |
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| المؤلفون: | Julian L. Fairey, Huong T. Pham, David G. Wahman |
| المصدر: | Environmental Science & Technology. 55:1740-1749 |
| بيانات النشر: | American Chemical Society (ACS), 2021. |
| سنة النشر: | 2021 |
| مصطلحات موضوعية: | Chloramine, Nitroxyl, General Chemistry, 010501 environmental sciences, 01 natural sciences, Decomposition, Medicinal chemistry, Unsymmetrical dimethylhydrazine, chemistry.chemical_compound, Peroxynitrous acid, chemistry, N-Nitrosodimethylamine, Environmental Chemistry, Dimethylamine, Dichloramine, 0105 earth and related environmental sciences |
| الوصف: | The N-nitrosodimethylamine (NDMA) formation pathway in chloraminated drinking water remains unresolved. In pH 7-10 waters amended with 10 μM total dimethylamine and 800 μeq Cl2·L-1 dichloramine (NHCl2), NDMA, nitrous oxide (N2O), dissolved oxygen (DO), NHCl2, and monochloramine (NH2Cl) were kinetically quantified. NHCl2, N2O, and DO profiles indicated that reactive nitrogen species (RNS) formed during NHCl2 decomposition, including nitroxyl/nitroxyl anion (HNO/NO-) and peroxynitrous acid/peroxynitrite anion (ONOOH/ONOO-). Experiments with uric acid (a ONOOH/ONOO- scavenger) implicated ONOOH/ONOO- as a central node for NDMA formation, which were further supported by the concomitant N-nitrodimethylamine formation. A kinetic model accurately simulated NHCl2, NH2Cl, NDMA, and DO concentrations and included (1) the unified model of chloramine chemistry revised with HNO as a direct product of NHCl2 hydrolysis; (2) HNO/NO- then reacting with (i) HNO to form N2O, (ii) DO to form ONOOH/ONOO-, or (iii) NHCl2 or NH2Cl to form nitrogen gas; and (3) NDMA formation via ONOOH/ONOO- or their decomposition products reacting with (i) dimethylamine (DMA) and/or (ii) chlorinated unsymmetrical dimethylhydrazine (UDMH-Cl), the product of NHCl2 and DMA. Overall, updated NHCl2 decomposition pathways are proposed, yielding (1) RNS via NHCl2→HNO/NO-→O2ONOOH/ONOO- and (2) NDMA via ONOOH/ONOO-→UDMH-ClorDMANDMA. |
| تدمد: | 1520-5851 0013-936X |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::25fd34f51b117ad39cf5e961dabf45ef https://doi.org/10.1021/acs.est.0c06456 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi...........25fd34f51b117ad39cf5e961dabf45ef |
| قاعدة البيانات: | OpenAIRE |
Find this issue from the American Chemical Society | تدمد: | 15205851 0013936X |
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