IEC 131 |
| James T. Nurmi and Paul G. Tratnyek. Department of Environmental and Biomolecular Systems, Oregon Health & Science University, 20000 NW Walker Road, Beaverton, OR 97006 |
| Polished iron disk electrodes provide a controlled model system that has proven to be a powerful tool in studies of contaminant reduction by zero-valent metals. To investigate the effects of particle size on reactivity of metals with contaminants, we have adapted the rotating disk electrode to accommodate fine powders (micro- to nano-meter grain sizes) of metals, metal oxides, and bimetallics. Using this powder cavity electrode, we have characterized a range of iron-containing powders (specific surface areas 1.0 - 50 m2/g) for reactivity with water and dissolved contaminants (e.g., carbon tetrachloride and nitrobenzene). Analysis of the current-potential data using mixed potential theory allows us to resolve rate constants for individual half-reactions. These data will be compared to kinetic data obtained from traditional batch and column experimental designs. Our method also appears to be very sensitive to particle structure and composition, which provides an interesting complement to commonly-used ex situ material characterization methods. |
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Nanotechnology and the Environment
5:00 PM-7:00 PM, Tuesday, March 25, 2003 Convention Center -- Hall G, Poster
Division of Industrial and Engineering Chemistry |