GEOC 147 |
| Dimitri A. Sverjensky, Department of Earth and Planetary Sciences, Department of Earth and Planetary Sciences, The Johns Hopkins University, Baltimore, MD 21218 |
| Simultaneous consideration of metal adsorption, surface titration in the presence of metals, and electrokinetic experimental data referring to wide ranges of pH, ionic strength, and surface coverage provide powerful constraints on the stoichiometry of adsorption reactions when analyzed with the triple-layer surface complexation model. Results include the need for mutiple surface complexes of metals and the involvement of surface hydroxyls and protons in the reaction stoichiometry, all of which are currently difficult to obtain by any other means. This information can be integrated with the results of X-ray studies that provide information on the stoichiometry of individual surface complexes involving metals. In combination with crystal chemical and Born solvation theory and linear free energy correlations, the results permit prediction of the adsorption and speciation of many divalent metals on rutile under a very wide range of conditions. |
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Interfacial Phenomena: Linking Atomistic and Macroscopic Properties
8:05 AM-11:30 AM, Wednesday, March 31, 2004 Marriott -- Marquis NW, Oral
Division of Geochemistry |