Process Of Separating And Recovering Copper, Nickel And Iron Rom Slag Containing Copper And Nickel

Slag containing copper and nickel produced by smelting process takes up a lot ofland and pollutes the surrounding environment, and can`t make full use of copper,nickel. At the same time result in waste of resources, so it is vital significance torecycling valuable metals in the slag. In this study, the grades of the iron, copper, nickelin the slag are48.60%,2.89%,4.44%respectively. The work focus on the processes forextracting copper, nickel with sulfuric acid leaching and microwave-aided leachingaccording to the feature of the slag. The two methods were compared through experimentof extracting copper, nickel from the slag containing copper and nickel, then theexperiments to modify the leaching process were carried out, and the following resultshave been obtained.The E-pH diagrams for the Cu-H₂O system, Ni-H₂O system and Fe-H₂O system at373K were calculated using Factsage thermodynamics software. The concentrations ofthe ions and temperature value used in the calculation are close to that of the actualleaching process. The thermodynamic conditions for sulfuric acid were determinedaccording the E-pH. In addition, the standard Gibbs free energy change and enthalpies forreaction of leaching process were calculated and drawn.The main operating parameters that influence the performance of the sulfuric acidleaching and microwave-aided leaching were investigated by experiments. The optimalleaching conditions of the sulfuric acid leaching were determined to be: concentration ofH2SO47Vt%, the solid-liquid ratio6:1, the temperature of leaching368K, stir-leachingtime40min. Under the optimal leaching condition, the leaching rate for copper, nickelwere88.30%,86.19%respectively. The apparent activation energies of copper, iron were calculated, the apparent activation energies were11.09kJ mol-1、19.40kJ mol-1respectively. The dynamics processes of copper、iron of the direct sulfuric acid leachingand microwave-aided leaching were diffusion control. The leaching time of microwaveheating was60min, while direct sulfuric acid leaching was40min which was shortened33%compared to microwave heating leaching.