An Investigation on the Effects of Surface Activation and Acidic Pretreatment on Ilmenite Recovery

Application of flotation in ilmenite fine particles recovery was not proved promising in previous studies, due to very limited active sites on ilmenite which is responsible for poor flotability of the mineral. In this work, surface activation and acidic pretreatment were examined to improve ilmenite floatability. Experiments were conducted on samples collected from the feed to line 3, containing 6.36% TiO2. The samples were ground to minus 106µm. Taguchi method was used to design experiments leading to optimal operational conditions, which found to be 700 g/t Clarient Flotinor SM 15 and Flotinor FS mixture with ratio 1/1 as collectors, 15 minutes as conditioning time and pH at 8.5. It is shown that using Pb(NO3)2 as surface activation with dosages up to 150 g/t, resulted in about 50% increase in recovery with a corresponding 9% increase in separation efficiency. Additionally, the concentrate grade was increased about 14% by using acidic pretreatment before conditioning.