The application of poly (sodium 4-styrene sulfonate) as an efficient dolomite depressant in the direct flotation of apatite from dolomite

Poly (sodium 4-styrene sulfonate) was tested as a novel and efficient depressant for the selective flotation of apatite and dolomite in this work. The separation performances were evaluated and the interaction mechanisms were uncovered. Flotation results illustrated that PSS strongly depressed dolomite, while it hardly affected the flotation of apatite. Zeta potential and Fourier Transform Infrared Spectrometer results indicated that the adsorption of PSS on dolomite was more favorable than that on apatite, which impeded sodium oleate to adsorb on dolomite surface and rendered it hydrophilic. XPS results indicated that -SO3- groups of PSS strongly complexed with both Ca2+ and Mg2+ sites on dolomite surface, but PSS weakly interacted with apatite surface and hardly affected the adsorption of NaOL on apatite surface. PSS exhibited excellent selectivity and environmental compatibility, which could simplify the flotation processes in upgrading phosphate ores through one-step direct flotation.