Investigation of solid-state carbothermal reduction of fayalite with and without added metallic iron

For every ton of pyrometallurgical Cu 2-3 t of Cu slag are generated, amounting globally to 4 000 000-5 000 000 t/a containing 35-45% Fe and 25-35% SiO2. An isothermal study of the solid-state reduction kinetics of fayalite with and without the addition of 10 wt% metallic Fe found that the carbothermal reduction is controlled by phase boundary reaction and that adding Fe decreases the activation energy from 165.22 to 145.74 kJ/mol. The fayalite decomposes into metallic Fe and quartz solid solution, the latter being converted into cristobalite solid solution with increasing temperature. The addition of metallic Fe creates a nucleating effect that accelerates the decomposition.
For every ton of pyrometallurgical Cu 2-3 t of Cu slag are generated, amounting globally to 4 000 000-5 000 000 t/a containing 35-45% Fe and 25-35% SiO2. An isothermal study of the solid-state reduction kinetics of fayalite with and without the addition of 10 wt% metallic Fe found that the carbothermal reduction is controlled by phase boundary reaction and that adding Fe decreases the activation energy from 165.22 to 145.74 kJ/mol. The fayalite decomposes into metallic Fe and quartz solid solution, the latter being converted into cristobalite solid solution with increasing temperature. The addition of metallic Fe creates a nucleating effect that accelerates the decomposition.