ABSTRACT The concentration of uranium in uranium‐bearing pregnant solution is a key parameter reflecting the efficiency of in situ leaching for uranium mining and is usually at the mg/L level. Current methods face difficulties in obtaining the species and concentration of uranyl complexes in the pregnant solution at the mg/L level quickly and nondestructively. In this work, an analytical method for species identification and concentration detection at the mg/L level of uranyl complexes was proposed based on quantitative Raman spectroscopy. Using the pregnant solution from the CO 2 + O 2 in situ leaching as the standard sample, the Raman quantitative relationships of uranyl complex concentrations in the pregnant solution were established. The results show the following: Based on Raman spectroscopy, uranyl dicarbonate UO 2 (CO 3 ) 2 2− and uranyl tricarbonate UO 2 (CO 3 ) 3 4− can be quickly identified. Using water as the internal standard, the concentrations of both UO 2 (CO 3 ) 2 2− and UO 2 (CO 3 ) 3 4− are in the linear relationship with the peak height ratio of the Raman peaks, which can be used to detect the concentration of uranyl complexes in the low‐concentration pregnant solution.
Yu et al. (Thu,) studied this question.