Abstract:UP to now,the leaching of manganese carbonate ore was usually performed at high temperature up to 363 K but leaching rate was lower than 90%.Even in laboratory test,the leaching rate was only about 90%.Therefore an improved method for more effective leaching of manganese carbonate ore was introduced,that is a certain amount of ammonium salt was added to the pulp to raise the solubility of Mn²⁺ and reduce the adsorption quantity of Mn²⁺ on the ore surface.Experimental results showed that a leaching rate over 95% could be obtained at the temperature 273K.The activation energy was calculated to be 7.15 kJ/mol,which is lower than that of normal leaching technique.Meanwhile a kinetic model was deduced,and verified with experiments,showing that the model could describe the leaching process successfully.

Key words: leaching; manganese ore; kinetics; model