A Study on the Recovery of Titanium Dioxide from a Blast Furnace Slag, Using Roasting and Acid Leaching

Abstract

In this research, parameters affecting the recovery of titanium dioxide from Iron slag sample collected from Esfahan Steel Company, located in Esfahan province, Iran, were studied. Roasting with sodium carbonate followed by sulfuric acid leaching was used in this study. The best condition for roasting with sodium carbonate was obtained at the temperature of 500oC with Na2CO3/slag ratio of 1/4, and in 120 minutes. The optimum condition for titanium dioxide recovery from iron blast furnace slag was achieved at temperature of 85oC, Solid/Liquid ratio of 1/15, sulfuric acid concentration of 2 M in 240 minutes time, for -106µm sized sample. The maximum recovery was 53%. The kinetic study showed that the leaching process was controlled by the diffusion, in which the activation energy was 5.85kJ/mol which confirmed the diffusion control of the process.