Abstract: The copper-bearing minerals in the copper sulfide ore in the Jiama area of Tibet are mainly composed of secondary copper sulfide minerals with low content. The ore was bioleached using the column leaching method of Thiobacillus ferrooxidans and the leaching kinetics was studied. For different ore grades， the effects of particle size on copper leaching rate and leaching ratio were investigated. The leaching ratio and the control equation in the shrinkage nucleus model were fitted to determine the speed control link in the leaching process. The test results show that the leaching rate and leaching ratio of copper increase with the decrease of the grain size. The SEM of the surface morphology of the ore indicates that the product layer containing jarosite is formed on the surface of the ore during the leaching process， which hinders the progress of the leaching reaction. The leaching kinetics indicates that the leaching process of the ore is conformed to the shrinkage nucleus model， which is mainly controlled by the diffusion within the solid product layer.

Key words: copper sulfide ore, Thiobacillus ferrooxidans, particle size, bioleaching kinetics, rate-controlling mechanism