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The influences of Ag, Bi, Sb and Zn impurities on the electrochemical adsorption of butyl xanthate on a galena surface were investigated. The impurity-doped and pure galena samples were synthesised by chemical precipitation and tested by X-ray diffraction (XRD) analyses. The flotation results suggest that the Ag and Bi impurities can promote the flotation of galena, while the Zn and Sb inhibit it. Both the lead- and impurity-xanthate are observed on the galena surface by infrared spectra, which suggests that the impurities on galena surface also interact with xanthate. However, Ag-xanthate and Bi-xanthate at the galena surface doped Ag or Bi may need to be further verified. The cyclic voltammetric measurements on galena microelectrodes reveal two oxidation peaks for both the pure and impurity-doped PbS, while no obvious reduction peaks are observed. It is found that the presence of Ag and Bi enhances the oxidation of xanthate on the galena surface, while the Zn and Sb impurities inhibit the oxidation of xanthate on the galena surface. The amount of electrochemically adsorbed xanthate on the galena surface varies based on the type of impurity and has a positive correlation with the flotation recovery of galena. [ABSTRACT FROM AUTHOR]

[Display omitted] • Galvanic interaction between chalcopyrite and galena has been studied by DFT method. • Galvanic interaction weakens the bonding DOS of O-Fe bonds, S-Cu bonds and S-Fe bonds. • Oxidation peak of electrode with a mix of chalcopyrite and galena is weaker than pure. Chalcopyrite is often associated with galena in nature, which brings great difficulties to the flotation recovery of chalcopyrite. One of the main reasons for these difficulties is that galvanic interaction between chalcopyrite and galena has a significant effect on the oxidation and flotation behavior of chalcopyrite. In this paper, density functional theory and cyclic voltammetry measurement were used to study galvanic interaction between chalcopyrite and galena and its effect on the adsorption of oxygen and xanthate molecules on chalcopyrite (0 0 1) surface. The results show that the galvanic interaction inhibits the dissociation of oxygen molecules on the surface of chalcopyrite (0 0 1), and it also weakens the bonding DOS of O-Fe bonds, S-Cu bonds and S-Fe bonds, which may be detrimental to the adsorption of xanthate and oxygen molecules on the surface of chalcopyrite (0 0 1). The cyclic voltammetry measurements results show that compared with pure chalcopyrite and pure galena electrode, the oxidation peak intensity of the electrode with a mass ratio of chalcopyrite and galena of 1:1 near 0.4 V is weaker at pH 9.18 and a butyl xanthate concentration of 0.001 mol/L, which is consistent with the results of DFT studies. [ABSTRACT FROM AUTHOR]