Viscosity of TiO2-FeO-Ti2O3-SiO2-MgO-CaO-Al2O3 for High-Titania Slag Smelting Process
The present study demonstrates the dependence of viscosity on chemical composition and temperature of high-titania slag, a very important raw material for producing titanium dioxide. The results indicated that completely molten high-titania slag exhibits a viscosity of less than 1 dPa s with negligible dependence on temperature. However, it increases dramatically with decreasing temperature slightly below the critical temperature, i.e., the solidus temperature of the slag. Above the critical temperature, the slag samples displayed the same order of viscosity at 0.6 dPa s, regardless of their compositional variation. However, the FeO, CaO, and MgO were confirmed to decrease viscosity, while SiO2 and Ti2O3 increase it. The apparent activation energy for viscosity-temperature relation and liquidus temperature based on experiments and thermodynamic calculations are also presented. Conclusively, the critical temperatures of the slags are on average 15 K below their corresponding calculated liquidus temperatures. The increase in FeO content was found to considerably lower the critical temperature, while the increase in both Ti2O3 and TiO2 contents increases it. The main phases of the slag in solid state, as indicated by X-ray diffraction, are (Fe, Mg)xTiyO5 (x + y = 3, pseudobrookite) and rutile.
The authors are especially grateful to the Natural Science Foundation of China (No: 51374262). The chemical compositions analysis of all the samples was performed by Panzhihua Iron and Steel Research Institute.
- 1.D.M. Glen and A.F. Schoukens. Production of High Titania Slag From Ilmenite. CA, 1993.Google Scholar
- 9.G.Z. Deng and X.F. Wang, Iron Steel Vanadium Titanium 2002, vol. 23, pp. 14-17.Google Scholar
- 10.V.A. Reznichenko, M.B. Rapoport and V.A. Tkachenko: The metallurgy of titanium : investigation of electric melting of titanium slags, English Translation, U.S. Dept. Commerce, 1963.Google Scholar
- 11.M.G. Frohberg and R. Weber, Arch Eisenhueeenw 1965, vol. 36, pp. 477-480.Google Scholar
- 12.A.V. Bemst; C. Delaunois, Verres Refractaires 1966, vol. 20, p. 435.Google Scholar
- 13.J.K. Tuset. Tidsskrift for Kjemi Berfvesenog Metallurgi 1968, vol. 28, p. 232-240.Google Scholar
- 15.Z.J. Zhao, E.Q. Ma and Y.J. Lian, Iron Steel Vanadium Titanium 2002, vol. 23, pp. 36-38.Google Scholar
- 16.G.G. Qiang, Y.Y. Cheng, and Y.D. Xian, Iron Steel Vanadium Titanium 1987, vol. 1, p. 55–59+70.Google Scholar
- 20.J. M. A. Geldenhuis and P. C. Pistorius, J S Afr I Min Metall 1999, vol. 99, pp. 41-47.Google Scholar
- 22.G. Eriksson, A D. Pelton, E. Woermann and A. Ender, Cheminform 1997, vol. 100, pp. 1839-1849.Google Scholar
- 29.K. Zheng, Z.T. Zhang, F.H. Yang, and S. Sridhar: in Ninth International Conference on Molten Slags,Fluxes and Salts, 2012, pp 342–49.Google Scholar
- 30.D. Liang, Z.M. Yan, X.W. Lv, J. Zhang and C.G. Bai, Metallurgical & Materials Transactions B 2017, vol. 48, pp. 1-9.Google Scholar