Mineral-Water Interface Dynamics: The Complex Interactions of Redox Active Metals With Manganese Oxide Surfaces

矿泉水界面动力学：氧化还原活性金属与氧化锰表面的复杂相互作用

• 批准号: 9902996
• 负责人: Michael Hochella
• 金额: $ 21.48万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9902996&HistoricalAwards=false
• 关键词: Mineral; Water; Interface; Dynamics; Complex

Hochella9902996The underlying objective of this project is to advance the understanding of the interactions between various manganese oxide minerals and redox active, environmentally important aqueous metals, specifically cobalt and chromium. The specific goals in this study are: to characterize (for the first time) the atomic and electronic surface structure of certain manganese oxides (manganite, hollandite and pyrolusite) using scanning tunneling microscopy and spectroscopy; to describe redox interactions (including oxidation/reduction, sorption/desorption, and dissolution processes) between several manganese oxides (manganite, hollandite, pyrolusite, and birnessite) and aqueous Co(II) and Cr(III) using principally fluid-cell atomic force microscopy, Auger and X-ray photoelectron spectroscopies, and wet-chemical techniques, as well as scanning tunneling microscopy and spectroscopy; and to develop new models for these interactions which combine our observations and assessments with the excellent store of information already available for many of these aqueous metal - mineral interactions. The research performed in this project will allow us to address previously unresolved issues concerning environmentally important, redox-mediated mineral-water interface reactions. Such issues include surface heterogeneity, various temporal aspects, the role of near-surface absorption and diffusion, and specific structural, chemical, and physical factors that control aqueous metal oxidation efficiencies.

Hochella9902996该项目的基本目标是促进对各种锰氧化物矿物与氧化还原活性、对环境有重要影响的水金属之间相互作用的了解，特别是钴和铬。本研究的具体目标是：(首次)用扫描隧道显微镜和光谱学表征某些锰氧化物(锰矿、霍兰矿和软锰矿)的原子和电子表面结构；主要利用流体室原子力显微镜、俄歇和X射线光电子能谱以及扫描隧道显微镜和光谱技术来描述几种锰氧化物(锰矿、霍兰矿、软锰矿和水钠锰矿)与Co(II)和Cr(III)之间的氧化还原作用(包括氧化/还原、吸附/解吸和溶解过程)；并为这些相互作用开发新的模型，将我们的观察和评估与许多此类含水金属-矿物相互作用的优秀信息存储相结合。在这个项目中进行的研究将使我们能够解决以前未解决的问题，这些问题涉及对环境具有重要意义的氧化还原介导的矿泉水界面反应。这些问题包括表面异质性、各种时间方面、近表面吸收和扩散的作用，以及控制水中金属氧化效率的特定结构、化学和物理因素。