title: Environmental impacts of steel slag reused in road construction: a crystallographic and molecular (XANES) approach.
abstract: Basic oxygen furnace (BOF) steel slag is a residue from the basic oxygen converter in steel-making operations, and is partially reused as an aggregate for road constructions. Although BOF slag is an attractive building material, its long-term behaviour and the associated environmental impacts must be taken into account. Indeed BOF slag is mainly composed of calcium, silicon and iron but also contains trace amounts of potential toxic elements, specifically chromium and vanadium, which can be released. The present research focuses (i) on the release of Cr and V during leaching and (ii) on their speciation within the bearing phase. Indeed the mobility and toxicity of heavy metals strongly depend on their speciation. Leaching tests show that only low amounts of Cr, present at relatively high concentration in steel slag, are released while the release of V is significantly high. X-ray absorption near-edge structure (XANES) spectroscopy indicates that Cr is present in the less mobile and less toxic trivalent form and that its speciation does not evolve during leaching. On the contrary, V which is predominantly present in the 4+ oxidation state seems to become oxidized to the pentavalent form (the most toxic form) during leaching.
authors.affiliation: CEREGE, UMR 6635 CNRS, University Paul Cézanne, IFR 112 PMSE, Europôle Méditerranéen de l'Arbois, BP 80, 13545 Aix en Provence Cedex 04, France. chaurand@cerege.fr
authors.forename: Perrine
authors.initials: P
authors.lastname: Chaurand
authors.forename: Jerome
authors.initials: J
authors.lastname: Rose
authors.forename: Valérie
authors.initials: V
authors.lastname: Briois
authors.forename: Luca
authors.initials: L
authors.lastname: Olivi
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Hazemann
authors.forename: Olivier
authors.initials: O
authors.lastname: Proux
authors.forename: Jérémie
authors.initials: J
authors.lastname: Domas
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Bottero
mesh_terms: D002857:Chromium / Q000032:analysis*; D003252:Construction Materials / Q000592:standards*; D018360:Crystallography, X-Ray; D004777:Environment; D007220:Industrial Waste; D013057:Spectrum Analysis; D013232:Steel; D014639:Vanadium / Q000032:analysis*; D014965:X-Rays
chemical_list: D007220:Industrial Waste; D014639:Vanadium; D002857:Chromium; D013232:Steel