wAbstract
@The release of U from the mineral meta-autunite {Ca[(UO2)(PO2)](H2O)6} was evaluated using spectroscopy, aqueous geochemistry,
and electron microscopy in a minimal media with the dissimilatory
metal-reducing bacterium Shewanella putrefaciens 200R.
The onset of anaerobic conditions resulted in the rapid release
of U and phosphate to solution followed by the reprecipitation
of meta-autunite. Spectroscopy measurements (XANES) indicated
that the U was not released via reduction during the bacterial
incubations, but instead dissolution was promoted by uptake and
immobilization of P by the bacterial cells.Our results suggest
that U(VI) in grefractoryh P mineral phases may be mobilized from
U mill tailings and/or U disposal sites and that the nutrient
status (P) of the geologic setting may be a predictor for the
lability of U in these environments.
Keywords: Uranium; autunite; phosphate; Shewanella putrefaciens;
weathering; XANESx
Introduction
Materials and methods
@Mineral preparation
@Bacteria and cultivation methods
@Experimental and sampling methods
@Solid phase characterization
@XANES experiments
Results and discussion
Acknowledgments
References cited