Recovery of Iron from Copper Slag by Carbothermic Reduction and Magnetic Separation in the Presence of CaO

The carbothermic reduction of copper slag at the different binary basicity (CaO/SiO2 ) was carried out for recovering iron by wet magnetic separation. Calcium carbonate is found to be capable of improving the iron recovery, as well as increasing the particle size of metallic iron significantly. Experimental evidence showed that CaO reacted with SiO2 to form calcium silicate and FeO was liberated from the 2FeO.SiO2 , decreased the content of Fe in the slags, which improved the iron recovery during the magnetic separation. The final product, assaying 90.23%Fetotal (representing a metallization degree of 93.94%) and 0.58% Cu at the iron recovery of 85.70% was achieved at the basicity of 0.60, which can be briquetted as a burden material for weathering resistant steel making by electric arc furnace to replace part of scrap