As a development to previous work, the composition of the slag for review was based on the available work, namely TiO2 = 37.19wt%, SiO2 = 19.69wt%, and Al2O3 = 13.12wt%, at varying proportions of CaO (30- 0wt%) and MgO (0-30wt%). The objective of the current project was to investigate the phase equilibria and beneficiation of titaniferous slags to produce a saleable titania product. It is thus clear that the understanding of phase relations in titaniferous slags requires further development. However, literature on phase compositions of plant titaniferous slags are conclusive about the crystallisation of Mg(Al,Ti,V)2O4 in high MgO and Al2O3 bearing slags. The available phase equilibria data established in air for titaniferous slags is inconclusive about the possible crystallisation of the detrimental spinel. The understanding of phase relations in titaniferous slags is thus important in order to be able to implement a suitable fluxing strategy for the production of a treatable titaniferous slag with no inert spinel phase. The lack of interest in processing titaniferous slags to produce saleable titania materials is attributed to the presence of chemically inert phases, like the spinel solid solution that cannot be handled by the available titania slag upgrading technologies. These fluxed slags can contain as high as 20-40wt% TiO2 (titania). The titaniferous slag by-products are generally defined by the Ca-Mg-Al-Si-Ti-O system. Titanomagnetite is typically smelted in blast or electric furnaces in the presence of reductant and fluxes (dolomite and quartz) to produce a valuable vanadium bearing pig iron and a virtually valueless titaniferous slag. It generally contains economically appreciable reserves of vanadium and iron as well as significant contents of titanium. Titaniferous magnetite (titanomagnetite) offers a unique opportunity for the production of three valuable products from one resource.

Factsage equilibrium phase diagram