Optimization Of Leaching Process Of Refractory Copper-cobalt Ore

With the intensification of mineral mining,the resources of easy-to-handle copper and cobalt ore are decreasing,People began to turn their attention to refractory copper-cobalt ore.The reserves of this type of minerals are huge,and it is extremely economical to study the leaching process.In this experiment,refractory copper-cobalt ore was used as the research object.The sulfuric acid-Na2SO3 system and sulfuric acid-hydrogen peroxide system were used for reductive leaching,and the phase analysis of the leaching slag was carried out to find out the existence of refractory copper and cobalt in the leaching slag.Finally,the optimal process is determined by the test of reducing agent combined leaching process.The paper mainly draws the following conclusions:The elemental content analysis,XRD analysis and scanning electron microscope analysis of the raw materials were used to determine the copper and cobalt metal contents and the occurrence forms in the raw materials.The stable existence area of the main components in the raw materials was determined by drawingE-pH diagrams of Cu-H2O,Co-H2O,Fe-H2O series,and the main reactions occurring in the solution were thermodynamically calculated to judge the possibility of the reactions under experimental conditions.Sulfuric acid was used as the leaching agent,and Na2SO3 was used as the reducing agent.The optimal leaching process is:temperature 85?,time 6 h,liquid-solid ratio 3.5:1,and the amount of Na2SO3 added is twice the theoretical amount.Under these conditions,the leaching rate of copper reached 83.21%,and the leaching rate of cobalt reached 93.41%.Sulfuric acid was used as the leaching agent and hydrogen peroxide was used as the reducing agent.The best leaching process is:temperature 75?,time 4 h,the amount of hydrogen peroxide added is 3.5 times the theoretical amount,and the liquid-solid ratio is 5:1.Under this condition,the leaching rate of copper reached 95.43%,and the leaching rate of cobalt reached 93.16%.The leaching kinetics was studied,and the results showed that copper and cobalt leaching were controlled by internal diffusion.Research on the technology of combined leaching of reducing agents,The are three kind of processes of simultaneous addition including two reducing agents,stepwise addition and two-stage leaching.The results show that the effect of the two-stage leaching is the bestThe conditions of the first-stage leaching process were temperature 85?,time 6 h,liquid-solid ratio 3.5:1,and the amount of Na2SO3 added was twice the theoretical amount.The second-stage leaching process was performed at a temperature of 75?,time 120 minutes,the amount of hydrogen peroxide added was 2.4 times of the theoretical amount,the amount of sulfuric acid was 2 mol/L,and the liquid-solid ratio was 5:1.The final copper leaching rate was 96.08%,and the cobalt leaching rate was 97.13%.The results of iron removal experiments show that when the temperature is 80?,the pH is 3.5,and the time is 2 hours,the amount of sodium chlorate is 1.8 times the theoretical amount,the iron removal rate can reach 98.77%,and the iron content is less than 0.01 g/L.