The oxidation dissolution of uranium oxides in carbonate-peroxide aqueous solution

The dissolution behaviors of uranium oxides (UO 2 , U 3 O 8, and UO 2 (O 2 )·4H 2 O) and the dissolved species of uranium in the carbonate-peroxide solution were investigated by UV–vis absorption spectrometry and interpreted by a theoretically calculated spectrum. The results indicate that the same dominant species (UO 2 (O 2 )(CO 3 ) 2 4− ) in the solution was observed in spite of the differences among the three uranium oxides. Additionally, the dissolution of UO 2 (O 2 )·4H 2 O was found to be occurring much more rapidly in carbonate solution than those of UO 2 and U 3 O 8 . The concentration of dissolved uranium for UO 2 (O 2 )·4H 2 O in the carbonate-peroxide solution could reach about 300 g/L.