It suggests that the ferrous minerals can retard U(VI) migration in phosphate-rich groundwater through the adsorption and subsequent reduction processes.ДЄamrani, S.E., Gimenez, J., Rovira, M., Seco, F., Grive, M., Bruno, J., Duro, L.

Ferrous iron and U(VI) on the green rust surface were completely oxidized and reduced into Fe(III) and U(IV) after 7 d. Surface investigation on the reacted mineral with uranyl phosphates species were carried out by XPS. The thermodynamic equilibrium calculation showed that the stable uranyl species (uranyl tri-carbonate) were newly formed at the condition. min)) compared to the value in the absence of the ions.The kinetic constants of aqueous U(VI) were 8 and 13 times lower (0.492 Г— 10 -3 g/(mg

Effects of Ca 2+ and CO 3 2- at pH 7 were examined in terms of removal kinetic and capacity. The removal behaviors of the minerals were well fitted by pseudo-second order kinetic model (R 2 > 0.990) indicating the dominant removal process was chemical adsorption. The zeta potential measurement results implies that the better performance of green rust might be attributed to the favorable surface charge toward uranyl phosphate species. and the efficiencies of green rust were roughly 2 times higher than that of vivianite. Vivianite (Fe 3 2+(PO 4)2в™ёH 2O) and green rust ( 2-), ferrous containing minerals, could remove aqueous U(VI) in 5 min.

Iaea tecdoc 1218