Synchrotron-based microanalytical techniques for the chemical speciation of metals and radionuclides in environmental samples
- Univ. of Georgia/SREL, Aiken, SC (United States)
A major obstacle in developing realistic environmental risk assessment or in designing environmentally sound, yet cost effective chemical and biological remediation strategies has been the ability to properly characterize the distribution and chemical speciation of a contaminant metal or radionuclide in an environmental sample or waste form. Synchrotron based X-ray fluorescence spectroscopy (SXRF) and X-ray absorption spectroscopy (XAS) are non-invasive techniques that can be used to examine the distribution and chemical speciation of elements (Z {ge} 20) in moist heterogeneous samples under ambient temperature and pressure. Using a dedicated micro-probe beam line (X-26A) at the National Synchrotron Light Source, Brookhaven National Lab, we have conducted spatially resolved XAS studies on a variety of environmental samples and on samples produced in waste isolation and processing activities. Spatially resolved SXRF spectroscopy has been used to generate elemental distribution maps on a 5 {mu}m scale, providing information on elemental distributions and associations. In addition, spatially resolved X-ray absorption near edge structure (XANES) spectroscopy has provided detailed information on the oxidation states of U, Cr, Se, and other metals and metalloids in contaminated soils, biological samples, and in waste forms on regions as small as 40 Pin, with minimal sample manipulation. Furthermore, qualitative information on bonding environments of many of these contaminants has been deduced based upon the {open_quote}fingerprint{close_quote} or multiple scattering regions of the XANES spectra coupled with the elemental distribution maps generated by SXRF spectroscopy.
- OSTI ID:
- 466497
- Report Number(s):
- CONF-951017-; TRN: 96:005999-0029
- Resource Relation:
- Conference: 22. annual conference of the Federation of Analytical Chemistry and Spectroscopy Societies, Cincinnati, OH (United States), 15-20 Oct 1995; Other Information: PBD: 1995; Related Information: Is Part Of FACSS XXII - the 22nd annual conference of the Federation of Analytical Chemistry and Spectroscopy Societies; PB: 285 p.
- Country of Publication:
- United States
- Language:
- English
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