Chlorination and bromination of olefins: Kinetic and mechanistic aspects
| العنوان: | Chlorination and bromination of olefins: Kinetic and mechanistic aspects |
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| المؤلفون: | Li, Juan, Jiang, Jin, Manasfi, Tarek, von Gunten, Urs |
| المصدر: | Water Research, 187 |
| بيانات النشر: | Elsevier, 2020. |
| سنة النشر: | 2020 |
| مصطلحات موضوعية: | chlorine (cl-2), acid-mediated oxidation, free available chlorine (FAC), bromine (HOBr), olefin, chlorine (Cl2), chlorine monoxide (Cl2O), Br2O, disinfection by-products, bromine monoxide (br2o), absolute rate constants, drinking-water, chlorine monoxide (cl2o), bromate formation, bromine (hobr), free available chlorine (fac), hypobromous acid, aqueous chlorination, polycyclic compounds, hypochlorous acid, electrophilic aromatic-substitution, natural organic-matter |
| الوصف: | Hypochlorous acid (HOCl) is typically assumed to be the primary reactive species in free available chlorine (FAC) solutions. Lately, it has been shown that less abundant chlorine species such as chlorine monoxide (Cl2O) and chlorine (Cl2) can also influence the kinetics of the abatement of certain compounds during chlorination. In this study, the chlorination as well as bromination kinetics and mechanisms of 12 selected olefins (including 3 aliphatic and 9 aromatic olefins) with different structures were explored. HOCl shows a low reactivity towards selected olefins with species-specific second-order rate constants 103 M−1s−1). The reactivities of chlorine and bromine species towards olefins follow the order of HOCl < HOBr < Br2O < Cl2O ≈ Cl2. Generally, electron-donating groups (e.g., CH2OH- and CH3-) enhances the reactivities of olefins towards chlorine and bromine species by a factor of 3-102, while electron-withdrawing groups (e.g., Cl-, Br-, NO2-, COOH-, CHO-, -COOR, and CN-) reduce the reactivities by a factor of 3-104. A reasonable linear free energy relationship (LFER) between the species-specific second-order rate constants of Br2O or Cl2O reactions with aromatic olefins and their Hammett σ + was established with a more negative ρ value for Br2O than for Cl2O, indicating that Br2O is more sensitive to substitution effects. Chlorinated products including HOCl-adducts and decarboxylated Cl-adduct were identified during chlorination of cinnamic acid by high-performance liquid chromatography/high resolution mass spectrometry (HPLC/HRMS). Water Research, 187 ISSN:0043-1354 ISSN:1879-2448 |
| وصف الملف: | application/application/pdf |
| اللغة: | English |
| تدمد: | 0043-1354 1879-2448 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::02a2fe0925933d4dded311542fa4f1a1 https://hdl.handle.net/20.500.11850/445856 |
| Rights: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....02a2fe0925933d4dded311542fa4f1a1 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 00431354 18792448 |
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