Thermodynamics property and structure evolution of the TiO2-containing molten slag with different CaO/SiO2 ratio and TiO2 content

Abstract

The influences of temperature and compositions (TiO2 and CaO/SiO2) on thermodynamics properties and structural evolutions of TiO2-CaO-Al2O3-MgO-SiO2 slags were investigated in this work. The slag viscosities increased with decreasing the temperature and declined with adding TiO2. With the raising of CaO/SiO2 ratio, the viscosity decreased under high temperatures, while it increased with the temperature further decreased lower than 1420 °C. The enthalpy change of the slag increased with raising the temperature as well as the TiO2 content and reduced with the CaO/SiO2 ratio increasing. Both the liquidus temperature and break point temperature of the slags decreased with adding TiO2 and increased with raising the CaO/SiO2 ratio. Temperature had a significant effect on slag structure evolutions, which decreased the slag polymerization degree. With adding TiO2 and CaO/SiO2 ratio in slags, the slag structure stability was weakened by increasing the amount of simpler silicate and TiO6 units and reducing the proportion of complex Ti-O units. Both the temperature and compositions (TiO2 and CaO/SiO2) depolymerized the slag structure to decline the viscosity.