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ELECTRON TRANSFER MECHANISM AT THE SOLID-LIQUID INTERFACE OF PHYLLOSILICATES
Citation:
Bailey, G W. AND L. Yan. ELECTRON TRANSFER MECHANISM AT THE SOLID-LIQUID INTERFACE OF PHYLLOSILICATES. Presented at Clays and Clay Minerals Meeting, West Lafayette, IN, June 27-July 1, 1999.
Description:
Interfacial electron transfer processes on clay minerals have significant impact in natural environments and geochemical systems. Nitrobenzene was used as molecular probes to study the electron transfer mechanism at the solid-water interfaces of Fe-containing phyllosicates. For this purpose, the oxidation state of structural Fe in Wyoming montmorillonite and ferruginous smectite (SWa-1) were chemically altered. The structural ferric Fe was reduced by sodium dithionite in citrate-bicarbonate (CB) buffer solution under N2 at 70oC, with the excess reactants removed by centrifugation. Both untreated and reduced clay suspensions were reacted with nitrobenzene or benzoic acid water solutions. The UV/Vis spectra of the suspension were collected before and after reacting with the organic probe molecules. Spectral changes in both molecular probes were observed, indicating the presence of new chemical species. These spectral changes were interpreted to mean that electron transfer and free radical formation occurred.