Moreno Carolina, Baeza-Romero María-Teresa, Sanz Mikel, Gálvez Óscar, López Arza Vicente, Ianni James C, Espíldora Eva
Universidad de Castilla-La Mancha, Escuela de Ingeniería Industrial y Aeroespacial, 45071, Toledo, Spain.
Phys Chem Chem Phys. 2020 Mar 14;22(10):5625-5637. doi: 10.1039/c9cp05601g. Epub 2020 Feb 26.
The aqueous-phase and surface reactions of ozone (O) with iodide (I) in/on seawater have been recently found to be a strong atmospheric source of iodine. In addition, ozone also reacts with I in solid and aqueous sea-salt aerosol. However, the primary products of the heterogeneous reactions of ozone with I have not been clarified. In this paper, solid and aqueous KI aerosols have been exposed to ozone in an aerosol flow tube system and I and iodate (IO) concentrations have been measured by UV-Vis spectroscopy. The results of these experiments have been combined with a kinetic model to elucidate the primary products of the aqueous and surface reactions. The reaction of ozone with aqueous iodide has been inferred to originate different products depending on whether it occurs at the surface via O adsorption (product I) or in the aqueous phase via O solvation (product IO). The surface reaction of ozone with solid KI in the presence of water vapor forms KIO, and other species, which are likely to be gaseous. Although the reactions have been studied in aerosols, the results can be extrapolated to aqueous solutions as well.
最近发现，海水中/上海洋表面的臭氧（O）与碘化物（I）的水相反应和表面反应是大气中碘的一个重要来源。此外，臭氧还与固态和气态海盐气溶胶中的碘发生反应。然而，臭氧与碘的非均相反应的主要产物尚未明确。在本文中，固态和气态碘化钾气溶胶在气溶胶流动管系统中暴露于臭氧中，并用紫外可见光谱法测量了碘和碘酸盐（IO）的浓度。这些实验结果与动力学模型相结合，以阐明水相反应和表面反应的主要产物。据推测，臭氧与水相碘化物的反应会产生不同的产物，这取决于反应是通过臭氧吸附在表面发生（产物I）还是通过臭氧溶剂化在水相中发生（产物IO）。在有水蒸气存在的情况下，臭氧与固态碘化钾的表面反应会生成碘酸钾和其他可能为气态的物质。尽管这些反应是在气溶胶中进行研究的，但结果也可外推至水溶液。
