Synthesis of Ferroalloys via Mill Scale-Dross-Graphite Interaction: Implication for Industrial Wastes Upcycling

Mill scale and aluminum dross are the industrial wastes from steel industries, which have high concentrations of Fe2O3 Al2O3, respectively. This paper reports conversion reducible metal oxides in into an alloy via carbothermic reduction at 1550 °C. Scale were mixed with graphite three different C/O molar ratios 1, 1.5, 2 to produce a pellet. The pellets heated °C for up 6 h under argon atmosphere. By this method, reductions found proceed formed Fe–Si–Al–C that consists Fe3Al Fe3Si phases. presence Si came SiO2 dross. Levels Al increase increasing ratios. However, level was stabilize since 3 h, while increases time h. Unreacted had insignificant effect on ferroalloy formation. These results provide evidence Fe2O3-Al2O3-SiO2 system show novel method upcycling mill toward circular economy.