Effect of crystal chemistry and surface properties on ilmenite flotation behavior

The crystal chemistry, surface properties and flotation behavior of three ilmenite samples: IL-F (purchased from the mineral dealership of A. and F. Krantz), IL-Q (Qara-aghaj deposit, Iran) and IL-K (Kahnuj deposit, Iran) were investigated. The substitution of different amounts of Mg, Mn and V in the crystal structure of ilmenite was identified by microprobe analysis. Different amounts of hemoilmenite exsolution were observed inside all three ilmenite samples using SEM, electron microprobe and X-ray diffraction analyses. Using these analytical techniques, the titanite phase was found inside the IL-K ilmenite. The XPS analysis indicated that the contents of Fe3+ are 5.66, 5.33 and 3.72% for IL-F, IL-Q and IL-K, respectively which are in good agreement with the amounts of hemoilmenite exsolution. The IEP was determined to be 4.2, 5.4 and 6.3 for IL-F, IL-Qand IL-K, respectively. Using sodium oleate as a collector, the maximum flotation recovery was obtained at 78.4, 73.5 and 51.5% for IL-F, IL-Qand IL-K samples, respectively, at a pH range of 5 to 7 where iron cations are active ions. The IEP has a negative correlation with Fe3+ ions, collector adsorption density and ilmenite floatability. Mg and V have negative correlation with ilmenite flotation recovery. Si and Ca sourced mainly from the titanite phase affect the flotation recovery of ilmenite negatively. (C) 2015 Elsevier B.V. All rights reserved.