Study On Flotation Separation Between Hematite And Apatite

The Oolitic hematite is abundant in our country, however, this type iron resource has not been widely exploited for its finely-dissemination particle, complex mineral composition, large amount of associated clay mineral with low hardness (plenty of calcium and magnesium ions dissolve in flotation process) and high content of detrimental impurity apatite mineral. Starting with dephosphorization of oolitic hematite, fundamental flotation behavior of hematite and apatite was studied in this paper and effect of calcium ions, magnesium ions and iron ions on flotation separation of hematite and apatite in the system conditioned by sodium carbonate and sodium hydroxide. Mechanism of the three ions in flotation separation was investigated through zeta potential measurements, ICP measurements, infrared spectrum tests and flotation solution chemistry calculation. Main research results are as follows:1、Slurry pH and collector dosage exert a prominent influence on flotation recovery of hematite and apatite. Floatability of hematite and apatite is better when NaOH was used as pH regulator than that when Na2CO3as pH regulator. Floatability of hematite and apatite differ from each other considerably under acid and highly alkaline condition, thus enjoying prospect of separation.2、"Ion-molecular association complex of oleic acid" is primary component of sodium oleate in hematite flotation. Under alkaline condition, sodium oleate adsorb on apatite surface chemically by taking calcium ions as active sites of apatite surface and thus calcium oleate will be formed, which is the main reason for apatite flotation by sodium oleate.3、Under highly alkaline condition, calcium and magnesium ions can activate apatite flotation and inhibit hematite flotation. Iron ions will inhibit apatite flotation but exert little influence on hematite flotation. In "NaOH-metal ion" and "Na2CO3-metal ion" system, activation or inhibition of metal ions on flotation of apatite and hematite is related to the superiority component in balance system. Formation calcium and magnesium ions hydroxo complex increases active sites on apatite surface and thus activates its flotation; iron hydroxide sediment of iron ions will form and will not increase active sites on its surface.