Study of the Mechanism of the Fe-BHA Chelates in Scheelite Flotation

Scheelite associated with calcium-containing minerals such as calcite and fluorite is difficult to separate by flotation because of the Ca ions contained in mineral lattices, which cause scheelite have similar surface properties floatability gangue minerals. Traditional collectors oleic acid need add a large amount sodium silicate inhibitors, causes difficulties for settlement tailings. In addition, use benzohydroxamic (BHA), needs addition Pb(NO3)2 activator, can also environmental pollution. this paper, Fe-BHA, new collector containing iron complex, was studied investigate its ability scheelite, well BHA/FeCl3 ratio on flotations. single flotations, Fe-BHA showed significant difference recoveries calcite, recovery 77.03% at pH 8.0 16.69% same pH. The results roughing tests Xianglushan actual ore that (500 g/t BHA 200 FeCl3) 40 obtained satisfactory WO3 grade 1.56% 65.52%, were much higher than those or collector, but there still gap using activation collector. UV-Vis curves different ratios indicated chelates might several structural forms, when molar FeCl3 about 1.2:1, best result test. XPS analyses proved adsorption occurred, fitting peaks 2p O 1s it found mechanism acting sites through removal H2O from Ca-OH Fe-OH form Fe-O-H.