Speciation of Fe Compounds in Selected Calcareous Soils Using XANES Analysis. (6341)
Authors:
D.L. Harrell* - Louisiana State University Agriculture Center J.J. Wang - Louisiana State University Agriculture Center A. Roy - Louisiana State University
Abstract:
Synchrotron X-ray absorption near-edge structure (XANES) spectroscopy was applied to five calcareous soils of differing geological origins in order to characterize the Fe species present.
Speciation of Fe in soil residues after employing common chemical Fe extraction procedures was also evaluated. The Fe K-XANES spectral data for standards and soil samples were collected with a 0.3 eV step size and a 4 sec. integration time from 7095 – 7180 eV using a double-crystal monochromator and a multi-element detector in both transmission and fluorescence mode. Quantitative speciation was determined by employing principal component analysis (PCA) followed by least-squares combination fitting statistical analysis (LCF) of representative Fe K-edge spectra of common soil Fe mineral standards. A distinct spectral shift could also be seen between Fe(II) and Fe(III) species. The relative abundances of Fe species in the soils and soil residues will be presented.
Speaker Information: Dustin Harrell, Louisiana State University Agriculture Center, Louisiana State University Dept. of Agronomy and Enviornmental Management 104 Madison B. Sturgis Hall, Baton Rouge, LA 70803-2110; Phone: 225-578-1360; E-mail: [email protected]
Session Information: Tuesday, November 2, 2004, 4:00 PM-6:00 PM Presentation Start: 4:00 PM (Poster Board Number: 2410) Keywords: Fe; XANES; Calcareous; Soils
