Thermal processing of ilmenite and titania-doped haematite using microwave energy

Abstract

To test the potential for microwave processing of lunar materials the heating of ilmenite-rock mixtures, and TiO₂-doped haematite were investigated using microwave radiation, llmeniterich rocks will couple, without a coupling agent, to microwave radiation. The microwave experiments are repeatable. Attempts to couple TiO₂-doped haematite to microwave radiation were very successful, with susceptibility increasing with TiO₂ content. Scanning electron microscopy (SEM) showed increased grain size and particle size with increased TiO₂ content in the microwave-heated products of the haematite-TiO₂ system. The differences between microwave and furnace melts of ilmenite-rich rocks were also investigated. Petrographic analysis revealed a large amount of titanomagetite in microwave melts while furnace melts contained a large amount of haematite, but the cause of this difference is not fully understood.