Study On Pressure Leaching Of Chalcopyrite

As for the chalcopyrite raw material,to begin with,this study make use of XRD,XRF and chemical analysis to preliminary master the material content and elements;and then the direct leaching of chalcopyrite was studied,which include a series of factors such as stirring speed,particle size,oxygen partial pressure,sulfuric acid concentration,temperature,liquid solid ratio,surfactant dosage.On this basis,the kinetics of different temperature were analyzed and the leaching residues were characterized.The microwave activation pretreatment-pressure leaching of chalcopyrite was studied,which include the effect of activation temperature and heating time.The microwave activation chalcopyrite,unpretreated chalcopyrite and their leaching residues were characterized by XRD and SEM.The main results are as follows:The study indicates that the prior dissolution of Fe will cause the presence of CuS on the surface of chalcopyrite in the non-oxidizing leaching.While the O2 is necessary to the Cu leaching.The leaching rate of Cu increases with the increasing oxygen partial pressure at 150?.However oxygen partial pressure has little effect on chalcopyrite leaching at 180?.One of the most important factors to chalcopyrite leaching is the temperature.The particle size of chalcopyrite used in the study is less than 32um.Leaching after 180 minutes,the leaching rate of Cu is within 56%at 150?,while the rate can reach to 97%at 180?.When the chalcopyrite is leached by 0?20g/L sulfuric acid solution at 150?,the leaching rate of Cu increases to some extend with the increasing concentration of H2SO4 and the leaching rate of Fe increases simultaneous.When the temperature is 180?,the leaching rate of Cu decreases a little with the increasing concentration of H2SO4,while the leaching rate of Fe increases.The chalcopyrite leaching belongs to unreacted shrinking core model.Through the dynamic model fitting,it turns out that the dynamic model of the chalcopyrite leaching is mixed control.Through the presentation of the chalcopyrite leaching residue,it can be found that leaching product is Fe2O3.During the leaching process of chalcopyrite,CuFeS2 may be transformed to CuS and form the FeS2.Experimental results show that microwave are propitious to the leaching of chalcopyrite;By the improved of microwave activation temperature,it increases the iron leaching rate without oxidation,but it is not propitious to the leaching of copper.The copper leaching rate increases with the increasing of heating time at low temperature.By the way of microwave activation,there are defects such as cracks and holes,at the same time it deepens Fe and S oxidation degree on mineral surface,thus improving the performance of chalcopyrite oxidation leaching.