THERMAL CHARACTERIZATION OF A SPANISH RED MUD

A Spanish red mud was thermally characterized. Chemical and mineralogical composition were determined by XRF and XRD. The thermal events observed in the range from room temperature to 1300 degrees C were related to the sample composition. The first mass loss step was related to free water content, while many of the other processes were related to dehydration processes. It was found that most of the decomposition reactions of hydrohematite, ferrihydrite, aluminogoethite, boehmite, silicates and carbonates were strongly overlapping. It was also explained the formation of silicates and calcium titanate, which presence was confirmed at 1000 degrees C by XRD.