The Study Of Electrochemistry Flotation Behavior And Surface Adsorption Of Lead-antimony-zinc-iron Sulfides

The difficulty of separation of complicated lead-zinc-iron sulfides was that the flotability of these minerals were similar and affected each other seriously. The collectorless flotation (includes self-induced flotation and sulfur-induced flotation) and collector-induced flotation (ethyl xanthate, sodium diethyldithiocarbamate and ammonium dibuyldithiophosphate as collector respectively) of thelead-antimony-zinc-iron sulfides ore (pyrrhotite, jamesonite and marmatite) which from Dachang, Guangxi province, China was investigated. The relationship of flotation recovery and pulp potential and potential-pH range for three sorts of mineral flotation in different system was established in this paper. The separated potential range for three minerals was demonstrated.The research results showed that the separated potential range of pyrrhotite and jamesonite was narrower when self-induced flotation had been processing. The floatable area of marmatite was close to jamesonite, but not to pyrrhotite. The colectorless flotation of pyrrhotite and jamesonite could not be improved when sodium sulphide was added, but marmatite could be when pulp was at neutral and weakly alkaline by addition of small amount sodium sulphide. There were a range of potential in all collector-induced flotation for separation of the lead-antimony-zinc-iron sulfides ore. The range in sodium diethyldithiocarbamate-induced flotation was the most narrow.The oxidation mechanism of mineral surface in collectorless flotation or collector-induced flotation was studied by extraction of neutral sulphur from mineral surface, electrochemical measure, Fourier Transform Infrared (FTIR) spectroscopy analysis, Ultraviolet radiation spectrum analysis, Auger Electron Spectroscopy (AES) measure, X-ray Photoelectron Spectroscopy(XPS) measure etc. It has been shown that neutral sulphur was the primary hydrophobic entity on minerals surface in collectorless flotation. The adsorption reaction and the major adsorption product on the surface of sulfide minerals with the collector was established. The intensity of adsorption on minerals and flotation recovery depended on pulp potentials, but themajor adsorption product had not be changed.The flotation behavior and adsorption mechanism of three sorts of sulfide minerals was investigated in regulator system (lime, copper sulphate, sodium humic acid, new regulator RC). The man-made mixed ore was separated successfully. The results showed that pyrrhotite and jamesonite could not be separated well with lime, but be separated by new regulator RC. The marmatite and pyrrhotite activated by copper sulphate could be separated well with combination reagent of sodium humic acid and Ca2+. The reason that the flotation of marmatite be improved was that Zn and Fe in the crystal lattice of marmatite was replaced by Cu2+ when copper sulphate was added.The anthor would like to thank the National Science Foundation NO. 50234010.