Improved Flotation Separation of Sulfide Minerals by Synthesized Surfactant Based on Para-Position Methyl Effect

•Methyl effect based selective sulfinate surfactants (SPTS) of sulfide minerals are developed.•SPTS can separate galena from pyrite and adsorb onto the galena surface rather than pyrite.•The selectivity of SPTS causes by the synergistic effect of hydrophobicity and desolvation effect.•SPTS can destroy S⋯H hydrogen bonds and replace the water molecules on the galena surface.•SPTS cannot destroy FeO bonds between water molecules and pyrite surfaces and the adsorption fails.