Selective enrichment and separation of Ti-Fe enriched mineral from Ti-bearing electric furnace slag with metallic iron as carrier

Abstract

A new process of selective enrichment and separation of Ti-bearing minerals from the Ti-bearing electric furnace slag (TEFS) with metallic iron as carrier was proposed in this paper. The thermodynamic analysis, melting process and selective reduction were carried out, with an emphasis on the effects of Fe2O3/slag ratio and H2 partial pressure on the processes. The results indicated that the major Ti-bearing mineral in TEFS was pseudobrookite after adding Fe2O3 into the molten slag. In the selective reduction process, the pseudobrookite particle in the modified slag was selectively reduced to the magnetic Ti-Fe enriched mineral particle embedded with metallic iron. Then the magnetic Ti-Fe enriched mineral particle was separated from the nonmagnetic silicate particle in magnetic separation process. Finally, the Ti-Fe enriched mineral with 61.1 wt% TiO2 and 18.31 wt% Total Fe was obtained. Furthermore, the recovery ratio of TiO2 and Total Fe were 85% and 78.6%, respectively. The contents of CaO and SiO2 of the Ti-Fe enriched mineral were 1.4 wt% and 1.9 wt%, which were much less than that of TEFS. The Ti-bearing mineral in TEFS was effectively concentrated as using the new selective enrichment and separation method.