%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Lahrouch, F.
%A Baptiste, B.
%A Dardenne, K.
%A Rothe, J.
%A Elkaim, E.
%A Descostes, M.
%A Gérard, Martine
%T Uranium speciation control by uranyl sulfate and phosphate in tailings subject to a Sahelian climate, Cominak, Niger
%D 2022
%L fdi:010083224
%G ENG
%J Chemosphere
%@ 0045-6535
%K Uranium ; Mining wastes ; Uranium migration ; EXAFS spectroscopy ; Environment ; Uranyl phosphate ; Uranyl sulfate
%K NIGER ; ZONE SAHELIENNE
%K COMINAK
%M ISI:000704947900010
%N 2
%P 132139 [11 ]
%R 10.1016/j.chemosphere.2021.132139
%U https://www.documentation.ird.fr/hor/fdi:010083224
%> https://www.documentation.ird.fr/intranet/publi/2021-11/010083224.pdf
%V 287
%W Horizon (IRD)
%X Long-term uranium mobility in tailings is an environmental management issue. The present study focuses on two U-enriched layers, surficial and buried 14.5 m, of the tailings pile of Cominak, Niger. The acidic and oxidizing conditions of the tailings pile combined with evapotranspiration cycles related to the Sahelian climate control U speciation. Uraninite, brannerite, and moluranite as well as uranophane are relict U phases. EXAFS spectroscopy, HR-XRD, and SEM/WDS highlight the major role of uranyl sulfate groups in uranium speciation. Uranyl phos-phate neoformation in the buried layer (paleolayer) acts as an efficient trap for uranium.
%$ 038 ; 064 ; 020