APPLICATION OF THERMAL-ANALYSIS TECHNIQUES TO A SAMPLE OF RED MUD - ABY-PRODUCT OF THE BAYER PROCESS FOR MAGNETIC SEPARATION

In a sample of Red Mud, a by-product of the Bayer process, the reducti on of ferric oxides to elemental iron and magnetite, performed prior t o subjecting the sample to magnetic separation, was followed by thermo gravimetric and differential thermal analysis (TGA/DTA) in an oxidizin g atmosphere. The relative quantities of metallic iron and magnetite i n the reduced sample can be estimated from the oxidation thermogram; i n the case of the magnetic fraction, obtained via magnetic separation of the reduced sample, the absolute quantity of metallic iron and magn etite can be estimated from the relative thermogram.