Abstract
Since only the functional group on the head of traditional flotation collectors’ molecules is responsible for their selective attachment on the desired mineral particle surface, immobilizing these functional groups on parts of hydrophobic surface of polystyrene nanoparticles imparts them the ability to attach simultaneously to both mineral surface and air bubbles. In the case of phosphorite direct flotation, carboxyl-functionalized polystyrene nanoparticles (FPSNPs) are candidates for traditional fatty acid collectors’ replacement. However, a large collector dosage is required to achieve a satisfactory flotation performance, which hinders their large-scale adoption.In this work, FPSNPs synthesized by emulsion polymerization were evaluated as phosphorite flotation collectors. Their flotation performance was evaluated using fine siliceous phosphorite particles. It was found that a concentrate, assaying 30.2% P2O5 and 5.4% SiO2 with 62.5% P2O5 recovery, was achieved by a combination of rougher and scavenger flotation using 2000 g/tonne of vacuum dried FPSNPs and 1000 g/ tonne of sodium silicate. However, collector dosage can be reduced by 91% without compromising P2O5 recovery and grade, a concentrate grade assaying 31.3% P2O5 and 7.1% SiO2 with 59% P2O5 recovery was achieved by a combination of rougher and scavenger flotation using 167 g/tonne of ethanol-dispersed FPSNPs and 200 g/tonne of acidified sodium silicate.