Investigating the Release of Co-precipitated Uranium from Iron Oxides
Citable Link (URL):http://resolver.sub.uni-goettingen.de/purl?gs-1/8984
The removal of uranium (VI) in zerovalent iron permeable reactive barriers and wetlands can be explained by its association with iron oxides. The long term stability of this immobilized U is yet to be addressed. The presented study investigates the remobilization of U(VI) from iron oxides via diverse reaction pathways (acidification, reduction, complex formation) in the laboratory. Prior uranium co-precipitation experiments were conducted under various conditions. The addition of various amounts of a pH-shifting agent (pyrite), an iron complexing agent (EDTA) or an iron (III) reduction agent (TiCl3) yielded in uranium remobilisation to concentrations above the US EPA maximum allowed contaminant level (MCL = 30 mg/L). This study demonstrates that U(VI) release in nature will strongly depend on the conditions and the mechanism of its fixation by geological materials.
Manuskriptversion von 2006