Luo Tao, Pokharel Rasesh, Chen Tao, Boily Jean-François, Hanna Khalil
Université de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, F-35000Rennes, France.
Department of Chemistry, Umeå University, UmeåSE-901 87, Sweden.
Environ Sci Technol. 2023 Jan 10;57(1):214-221. doi: 10.1021/acs.est.2c05963. Epub 2022 Dec 5.
Predicting the fate and transport of pharmaceuticals in terrestrial environments requires knowledge of their interactions with complex mineral assemblages. To advance knowledge along this front, we examined the reactivity of pipemidic acid (PIP), a typical quinolone antibiotic, with quartz particles coated with a mixture of manganese oxide (MnO) and goethite (α-FeOOH) under static and dynamic flow conditions. Batch and dynamic column experiments showed that PIP binding to MnO proceeded through a heterogeneous redox reaction, while binding to goethite was not redox-reactive. Mixed columns of aggregated goethite-manganese particles however enhanced redox reactivity because (i) goethite facilitated the transport of dissolved Mn(II) ion and increased the retention of PIP oxidation products, and (ii) MnO was protected from passivation. This mobility behavior was predicted using transport models accounting for adsorption and transformation kinetics of PIP on both goethite and MnO. This work sheds new light on reactivity changes of mixtures of Fe and Mn oxides under flow-through conditions and will have important implications in predicting the fate and transport of redox-active organic compounds as well as development of new geomedia filters for environmental remediation.
预测药物在陆地环境中的归宿和迁移需要了解它们与复杂矿物组合的相互作用。为了在这方面推进知识，我们研究了典型喹诺酮类抗生素吡哌酸（PIP）在静态和动态流动条件下与涂有氧化锰（MnO）和针铁矿（α-FeOOH）混合物的石英颗粒的反应性。批量和动态柱实验表明，PIP与MnO的结合通过非均相氧化还原反应进行，而与针铁矿的结合则没有氧化还原活性。然而，聚集的针铁矿-锰颗粒混合柱增强了氧化还原反应性，因为（i）针铁矿促进了溶解的Mn（II）离子的迁移并增加了PIP氧化产物的保留，以及（ii）MnO受到保护而不被钝化。使用考虑PIP在针铁矿和MnO上的吸附和转化动力学的传输模型预测了这种迁移行为。这项工作为流动条件下铁和锰氧化物混合物的反应性变化提供了新的见解，并将对预测氧化还原活性有机化合物的归宿和迁移以及开发用于环境修复的新型地质介质过滤器具有重要意义。
