UNS: The Oxidative Potential of Manganese Oxides in Passive Water Treatment Systems

天然存在的和合成的锰氧化物是最强的天然氧化剂之一，可以破坏有害的有机化合物。有机化合物广泛存在于水污染物中，包括许多内分泌干扰化合物、生物活性激素和抗生素。传统的一级和二级废水处理技术一般不能去除这些化学物质，也不能显著降解这些化学物质，导致它们排放到饮用水水源，包括地表水和地下水中。因此，本项目的重点是探索锰氧化物作为廉价的被动氧化剂的使用，以去除水中的各种有机污染物。本研究的目的是：(1)评估目标有机化合物与锰氧化物的反应性；(2)研究环境条件对锰氧化物反应性的影响。pi将(1)评估目标有机化合物（例如，模型酚类和酚类污染物）与δ mno2（一种纯Mn（IV）氧化物）和从饮用水处理系统收集的先前未表征的锰固体的反应性和转化机制，同时量化固相氧化锰的化学变化；(2)量化在污染物氧化过程中溶解的O2在限制氧化锰表面钝化中的作用；(3)量化竞争反应对目标污染物转化的影响。所提出的工作将对管理锰氧化物在环境中降解有机污染物的能力的基本和实际考虑产生重要的见解。由于其高反应性，锰氧化物可用于去除各种水处理应用中的顽固性有机污染物。例如，基于氧化锰的过滤介质可用于绿色基础设施，如生物滞留池、透水路面、绿色屋顶和植被洼地，以氧化城市雨水中的各种污染物。类似地，可以在土工合成或粘土衬垫下面安装一层氧化锰，这些衬垫通常用于容纳垃圾填埋场或粪肥泻湖的渗滤液。该项目每年夏天将为一名研究生提供研究、教学和指导机会，并为一名本科生暑期实习生提供研究机会。

1509879Ginder-VogelNaturally occurring and synthetic manganese oxides are among the strongest, naturally occurring oxidants and can destroy hazardous organic compounds. Organic compounds are widespread among aqueous pollutants and include many endocrine disrupting compounds, biologically active hormones, and antibiotics. These chemicals are generally not removed nor significantly degraded by traditional primary and secondary wastewater treatment technologies, resulting in their discharge to and presence in drinking water sources, including surface and groundwater. Thus the focus of this project is to explore the use of manganese oxides as inexpensive passive oxidants to remove a variety of organic contaminants from water.The objectives of the proposed research are to: (1) assess the reactivity of target organic compounds with manganese oxides, and, (2) investigate the impact of environmental conditions on manganese oxide reactivity. The PIs will (1) assess the reactivity and transformation mechanisms of target organic compounds (e.g., model phenols and phenolic contaminants) with delta-MnO2 (a pure Mn(IV) oxide) and previously uncharacterized manganese solids collected from a drinking water treatment system, while quantifying changes in solid-phase manganese oxide chemistry, (2) quantify the role of dissolved O2 in limiting manganese oxide surface passivation during contaminant oxidation, and, (3) quantify the impact of competing reactions on target contaminant transformation. The proposed work will yield important insights into the fundamental and practical considerations that govern the ability of manganese oxides to degrade organic contaminants in environmental settings. Due to their high reactivity, manganese oxides could be applied to remove recalcitrant organic contaminants in a variety of water treatment applications. For example, manganese oxide-based filter media could be used in green infrastructure, such as bioretention ponds, permeable pavements, green roofs and vegetated swales, to oxidize a wide range of contaminants in urban stormwater. Similarly, a layer of manganese oxides could be installed below the geosynthetic or clay-based liners typically used to contain landfill or manure lagoon leachate. This project will provide research, teaching and mentoring opportunities for a graduate student and a research opportunity for an undergraduate summer intern each summer.