Microwave-based pyrometallurgical process to produce ferrosilicon with PV cells from EoL PV panels

In this work, PV silicon recovered from a PV panel recycling facility was utilized as a reactant for the synthesis of ferrosilicon alloys via microwave treatment in the presence of iron oxides and graphite. Microwave-driven process was further explored using ladle furnace slag from secondary steelmaking as a reactive component. Different amounts of reactants, time and microwave power were used. Microwave heating allowed to reach temperatures higher than 900 °C after few minutes of treatment at a power of 600 W. The obtained materials were characterized by SEM-EDS and XRD. The proposed process allowed to obtain a ferrosilicon alloy with an amount of 21% Si. This study explored the use of three different types of waste to obtain a ferroalloy FeSi that can be afterwards employed in the steelmaking process.