LAUSR

Abstract The production of pure TiO2 gains a lot of interest because of its use in white pigment, ink and cosmetics as well as precursor for Ti metal production. Although titanium oxide is commonly distributed in accessory minerals in hard rocks and sediments (rutile, anatase and brookite), ores with high amounts of TiO2-phases are not common. Important minable Ti ore often contains Fe Ti oxides like ilmenite or pseudorutile. A current processing route to produce high purity TiO2 out of these phases involves a hydrometallurgical step with concentrated sulfuric acid that is applied at high temperatures to leach preconcentrated iron containing Ti-ore. To overcome this energy intense current technology a novel method, called TiMAG-process has been developed at IFAD over the last few years. This process uses nascent hydrogen generated by the reaction of a base metal like Al with diluted H2SO4 at moderate temperatures together with ilmenite concentrate in a specific milling and leaching process aiming a reduction of Ti4+ to Ti3+. Recent investigations reveal, that mineralogical and chemical properties of Fe Ti oxide concentrates can distinctively influence their leaching, changing the transfer rate of Ti into the liquid phase under identical process conditions between 50 and 80%. Two major facts have been identified and will be discussed in this paper based on tests with Fe Ti oxide samples from India and Mozambique revealing some different physico-chemical properties.