Abstract:In order to study leaching performance of micro-acid neutral leaching process for high carbonate uranium ore, static leaching tests, multiple stirring oxidation leaching tests and column leaching tests were conducted on uranium ore from a high carbonate sandstone type uranium deposit. The test results show that application of traditional acidic leaching of high carbonate type uranium ore can easily produce gas plugging and CaSO4 precipitation, while the application of micro-acid neutral leaching will not easily produce precipitation although the leaching intensity is small, and leaching intensity of application of alkaline leaching is slightly higher than that of micro-acid neutral leaching, but it is easy to produce CaCO3 precipitation. Leaching efficiency of low concentration H2O2 oxidation is low, H2O2 is mainly consumed by other reducing substances in the ore, high concentration H2O2 is easy to react with uranium in solution to generate uranium peroxide precipitation, while KMnO4 oxidation leaching effect is obvious. In column leaching, leaching rate of micro-acid leaching and alkaline leaching is 49.2% and 41.7%, respectively. The main limiting factor of the former is that oxidation rate of column is lower than acidification rate of column, while the main limiting factor of latter is blockage of ore layer and drops of out permeability in late leaching period.