Pressure Leaching Kinetics of Complex Copper Sulfide Concentrate

The pressure leaching kinetics of copper sulfide concentrate with tetrahedrite as the main mineral is studied in the following conditions: the leaching temperature as from 408K to 453K,the initial sulfuric acid concentration as 1.23mol/L,the ratio of liquid to solid as 30/1(mL/g),the oxygen partial pressure as 0.6 MPa,the agitation speed as 500r/min.The experimental results show that the linear relationship between the leaching efficiency of copper,zinc,iron and the leaching time exits before the leaching equilibrium,respectively.The time consumed for which the leaching of copper and zinc arrives at the equilibrium is all shortened with the increase of leaching temperature and the leaching equilibrium of zinc is prior to that of copper.The leaching rate of both copper and zinc is increased with the increase of the temperature from 408K to 438K and the leaching rate of zinc is always higher than that of copper.But when the temperature is further raised at 453K,the leaching rate of zinc is not changed anymore while that of copper is raised greatly and higher than that of both zinc and iron.The apparent activation energy is determined as 71.98kJ/mol and 69.33kJ/mol for the leaching of copper and zinc,respectively.The leaching of both copper and zinc follows the shrinking core model with surface reaction control.