Abstract: In view of the difficulties in the process of cobalt reduction leaching of a copper-cobalt in Central Africa,such as low cobalt leaching rate,low utilization of SO2 gas,and environmental pollution caused by SO2 gas escape,according to the philosophy study of cobalt leaching with SO2 gas and field tests,the creative mode of SO2 gas pressurization and atmospheric pressure combination intervention is adopted by the intervention of three process routes into cobalt reduction and leaching reaction,and the supporting specialized equipment is developed. The new process and its specialized equipment significantly improve the solubility and utilization rate of SO2 gas by complete mixing of SO2 gas and solution and effective control of gas escape,accelerate the regeneration rate of reducing leaching agent Fe2+,and achieve efficient extraction of cobalt by enhancing the synergistic reduction and leaching of SO2 and Fe2+. The on-site test data showed that the new process and its specialized equipment can achieve an increase in the utilization rate of SO2 gas by above 15 percentage points,and a 3 percentage points increase in cobalt leaching rate. While increasing cobalt production capacity,it also reduces production cost and effectively solves the problem of environmental pollution caused by SO2 gas escaping. The study achievement can be used for optimization guidance of copper-cobalt mine enterprises in Central Africa and improve the existing production process of copper-cobalt minerals extraction by the hydrometallurgical process,significantly improve the leaching efficiency of cobalt,thus increasing the production capacity of cobalt,and reduce production cost by improving SO2 gas utilization rate.

Key words: copper-cobalt metallogenic belt in Central Africa,synergistic leaching,gas utilization rate of SO2,leaching rate of cobalt