Abstract:In order to investigate the leaching process parameters of a high carbonate sandstone type uranium ore, tatic leaching tests were carried out indoors with different alkaline reagents and different oxidants, the saturation index of carbonate minerals and the form of uranium present in leachate were calculated using PHREEQCI software, and leaching kinetic analysis was performed. The results show that leaching rate of uranium is positively correlated with the concentration of HCO3- in leachate，and the leaching effect of NH4HCO3 is better than that of NaHCO3. The oxidation effect of H2O2 is significantly stronger than that of KMnO4 and K3Fe(CN)6, and the leaching rate of uranium rises with increase of mass concentration of H2O2, and the best leaching conditions is 800 mg/L NH4HCO3 + 2 g/L H2O2, with a final uranium leaching rate of 21.04%. The pH value of the system should be controlled to avoid saturation precipitation of carbonate; the dissolution reaction of uranium during the leaching process is mainly controlled by surface chemistry, and the influence of diffusion is relatively small.