The Effect of Heat Treatment on Titania Slag

The paper embodies the influence of thermal treatment on the morphology, composition and leaching behaviour of titania slag. When Ti-slag was subjected to heat treatment, it developed pores and oxidized at high temperature. This slag consists mainly of a M3O5 phase with an orthorhombic structure. The decrepitation was studied by oxidizing the titania slag sample produced in a pot/muffle furnace at temperature 750 0 C. Sample oxidized at 750 0 C cracked while sample treated at further high temperature did not show any cracking. The cracking of the samples was linked to decrepitation of the slags which is evidenced from the development of pores in the surface of the sample. From the available information it is postulated that cracks occurs due to change in the crystal lattice of the M3O5 phase of the slag after oxidation. The present study is directed to a process for the upgrading of titania slags into a product having a very high TiO2 content with low levels of alkaline-earth and other impurities.