Wang Yan, Rodríguez Eva M, Rentsch Daniel, Qiang Zhimin, von Gunten Urs
School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Environ Sci Technol. 2025 Mar 11;59(9):4733-4744. doi: 10.1021/acs.est.4c07119. Epub 2025 Feb 28.
The temperature dependence of the kinetics and the mechanisms of ozone reactions with 19 olefins and 3 alkynes were investigated. The second-order rate constants () for ozone reactions with olefins were mostly in the range of 10-10 M s, with activation energies of 17.4-37.7 kJ mol. In comparison, alkynes had lower (∼10 M s) and higher activation energies (36.7-48.1 kJ mol). Reactivities of both olefins and alkynes are mainly influenced by inductive effects of substituents, with steric effects observed for cyclic olefins. 2-Buten-1,4-dial (BDA), synthesized with a novel method, is a toxic olefinic oxidation product from phenols. Its and -isomers show distinct reactivities with ozone, with (20 °C) of 3.0 × 10 and 1.2 × 10 M s, respectively. Two mols of glyoxal were formed per mol of ozonated BDA, with a slow release of the second mol from an α-hydroxyalkylhydroperoxide intermediate. 2-Ethynylbenzaldehyde reacts with ozone with a stoichiometry of 1:1 and (20 °C) = 1.6 × 10 M s. Ozone attacks the ethynyl group, yielding a carboxyl product (2-carboxybenzaldehyde, 54%), an aldehyde product (phthaldialdehyde), and a dicarbonyl product with a stoichiometric release of HO (21%). This study provides kinetic and mechanistic information for assessing the abatement of olefin- and alkyne-containing micropollutants by ozonation at various temperatures.
研究了臭氧与19种烯烃和3种炔烃反应的动力学及反应机理的温度依赖性。臭氧与烯烃反应的二级速率常数（）大多在10⁻¹⁰ M⁻¹ s⁻¹范围内，活化能为17.4 - 37.7 kJ mol⁻¹。相比之下，炔烃的二级速率常数较低（约10⁻¹¹ M⁻¹ s⁻¹），活化能较高（36.7 - 48.1 kJ mol⁻¹）。烯烃和炔烃的反应活性主要受取代基的诱导效应影响，环状烯烃则存在空间效应。通过新方法合成的2-丁烯-1,4-二醛（BDA）是酚类产生的有毒烯烃氧化产物。其顺式和反式异构体与臭氧反应表现出不同的反应活性，20℃时的二级速率常数分别为3.0×10⁻¹⁰和1.2×10⁻¹¹ M⁻¹ s⁻¹。每摩尔臭氧化的BDA生成两摩尔乙二醛，第二摩尔乙二醛从α-羟烷基氢过氧化物中间体缓慢释放。2-乙炔基苯甲醛与臭氧按化学计量比1:1反应，20℃时的二级速率常数为1.6×10⁻¹¹ M⁻¹ s⁻¹。臭氧攻击乙炔基，生成羧基产物（2-羧基苯甲醛，54%）、醛产物（邻苯二甲醛）和化学计量释放HO的二羰基产物（21%）。本研究提供了动力学和反应机理信息，用于评估在不同温度下通过臭氧化去除含烯烃和炔烃的微污染物。
