Effects of Basicity and MnO on Perovskite Precipitation in Medium-Titanium Blast Furnace Slag

Abstract In order to further enrich and utilize titanium in medium-titanium blaster slag, the effects of basicity and additive MnO on perovskite precipitation were investigated, and the mechanism of basicity and additive MnO was preliminarily discussed. Thermodynamic and kinetic analysis of perovskite enrichment in medium titanium slag was carried out by FACTSage8.3 thermodynamic software and molecular dynamics software, and experimental verification was carried out by selective precipitation and enrichment technology. The results showed that: basicity has an effect on the precipitation and growth of perovskite in medium-titanium blast slag. When basicity is 1.3, (with 6.19% CaO added), the crystal size and volume fraction of perovskite phase crystals reach large values, 18.96 μm and 6.24%, respectively. Under the condition of basicity of 1.3, adding different contents of MnO, when adding 0.5% MnO, the particle size and volume fraction of perovskite in titanium slag reached the maximum at the same time, which were 25.31 μm and 7.02%, respectively. The experimental results are well verified with the thermodynamic and kinetic theory analysis, and the effective enrichment of Ti in the titanium-containing blast-furnace slag is realized. The enrichment rate (i.e., the degree or level of enrichment) of the blast-furnace slag with 0.5% MnO is increased by 79.23% compared with the blast-furnace slag with only changing basicity.