Abstract:The influence of surface dissolution on flotation separation of fine ilmenite from titanaugite was investigated through  infrared spectroscopic (FT-IR) analysis and X-ray photoelectron spectroscopy (XPS) test. The results show that surface dissolution in weak acid solution is helpful to enlarge the floatability difference between ilmenite and titanaugite. In weak acidic solution, as sodium oleate mainly interacts with Fe which results in ilmenite flotation, and surface dissolution is beneficial to its oxidation, the floatability of ilmenite after surface dissolution is increased; meanwhile, sodium oleate interacts with Ca and Mg which results in titanaugite flotation, and the quantities of Ca and Mg on the surface of titanautite are decreased due to the surface dissolution, so the floatability of titanaugite after surface dissolution is depressed. For an ilmenite ore obtained from Panzhihua with TiO₂ grade of 8.41%, flotation after surface dissolution treatment could increase TiO₂ grade of rough concentrate from 26.7% to 31.73%.

Key words: ilmenite; titanaugite; flotation; surface dissolution