title: New methodological approach for the vanadium K-edge X-ray absorption near-edge structure interpretation: application to the speciation of vanadium in oxide phases from steel slag.
abstract: This paper presents a comparison between several methods dedicated to the interpretation of V K-edge X-ray absorption near-edge structure (XANES) features. V K-edge XANES spectra of several V-bearing standard compounds were measured in an effort to evaluate advantages and limits of each method. The standard compounds include natural minerals and synthetic compounds containing vanadium at various oxidation state (from +3 to +5) and in different symmetry (octahedral, tetrahedral, and square pyramidal). Correlations between normalized pre-edge peak area and its centroid position have been identified as the most reliable method for determining quantitative and accurate redox and symmetry information for vanadium. This methodology has been previously developed for the Fe K edge. It is also well adapted for the V K edge and is less influenced by the standard choice than other methods. This methodology was applied on an "environmental sample," i.e., a well-crystallized leached steel slag containing vanadium as traces. Micro-XANES measurements allowed elucidating the microdistribution of vanadium speciation in leached steel slag. The vanadium exhibits an important evolution from the unaltered to the altered phases. Its oxidation state increases from +3 to +5 together with the decrease of its symmetry (from octahedral to tetrahedral).
authors: CEREGE UMR CNRS/Université Paul Cézanne Aix-Marseille III, Europôle de l'Arbois, BP80, 13545 Aix en Provence Cedex 4, France. chaurand@ cerege.fr
authors: Perrine
authors: P
authors: Chaurand
authors: Jérôme
authors: J
authors: Rose
authors: Valérie
authors: V
authors: Briois
authors: Murielle
authors: M
authors: Salome
authors: Olivier
authors: O
authors: Proux
authors: Vivian
authors: V
authors: Nassif
authors: Luca
authors: L
authors: Olivi
authors: Jean
authors: J
authors: Susini
authors: Jean-Louis
authors: JL
authors: Hazemann
authors: Jean-Yves
authors: JY
authors: Bottero