SIMS AND SIMS IMAGING STUDIES OF ADSORBED DIALKYL DITHIOPHOSPHINATES ON PBS CRYSTAL-SURFACES

Secondary Ion Mass Spectrometry (SIMS) has been used to study the surf aces of natural galena (lead sulfide) crystals treated with a homologo us series of dialkyl dithiophosphinates. The semi-quantitative adsorpt ion data, as a function of pH, obtained from the near static SIMS meas urements using the fragment ions attributable to the dithiophosphinate s are consistent with that expected from actual mineral flotation data . Imaging experiments using reagent fragment ions under non-static SIM S conditions allowed mapping of dithiophosphinate species on crystal f aces of plena. Contrary to what might be expected, non-uniform dithiop hosphinate adsorption was observed. The very high sensitivity relative to other surface analytical techniques, and the imaging capability of SIMS, make it a valuable tool to study monolayer and submonolayer ads orption of surfactants on solids.