Role of trivalent antimony in the removal of As, Sb, and Bi impurities from copper electrolytes

Abstract

The role of trivalent antimony was investigated in removing As, Sb, and Bi impurities from a copper electrolyte. Purification experiments were carried out by adding a various concentrations of Sb(III) ions in a synthetic electrolyte containing 185 g/L sulfuric acid, 45 g/L Cu²⁺, 10 g/L As, and 0.5 g/L Bi under stirring at 65°C for 2 h. The electrolyte was filtered, and the structure, morphology and composition of the precipitate were analyzed by means of chemical analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and IR spectroscopy. The precipitate is composed of irregular lumps which are agglomerated by fine dendritic and floccus particles, and it mainly consists of As, Sb, Bi, and O elements. Characteristic bands in the IR spectra of the precipitate are As-OX (X=As, Sb, Bi), Sb-OY (Y=Sb, Bi), O-As-O, As-OH, Sb-OH, and O-H. The precipitate is a mixture of microcrystalline SbAsO₄, (Sb,As)₂O₃, and amorphous phases. As, Sb, and Bi impurities are effectively removed from the copper electrolyte by Sb(III) ions attributing to these precipitates.

Keywords

copper metallurgy / electrorefining / electrolytes / impurities / removal / antimony / arsenic / bismuth

References

[1] Navarro P., Simpson J., Alguacil F.J. Removal of antimony (III) from copper in sulphuric acid solutions by solvent extraction with LIX 1104SM. Hydrometallurgy, 1999, 53(2): 121.

[2] Wang X.W., Chen Q.Y., Yin Z.L., Wang M.Y., Xiao B.R., Zhang F. Homogeneous precipitation of As, Sb and Bi impurities in copper electrolyte during electrorefining. Hydrometallurgy, 2011, 105(3–4): 355.

[3] Navarro P., Alguacil F.J. Adsorption of antimony and arsenic from a copper electrorefining solution onto activated carbon. Hydrometallurgy, 2002, 66(1–3): 101.

[4] Xiao F.X. Novel Technology of Purification of Copper Electrolyte and Basic Research [Dissertation], 2008, Changsha, Central South University

[5] Xiao F.X., Zheng Y.J., Wang Y., Xu W., Li C.H., Jian H.S. Novel technology of purification of copper electrolyte. Trans. Nonferrous Met. Soc. China, 2007, 17(5): 1069.

[6] Y. Wen, Y.Z. Sheng, and S. Zhang, The controls of impurities distribution in copper electrolysis process, [in]_The Symposium of Production Technology, Equipment, Materials and Market of National Copper Nickel and Cobalt, Beijing, 2003, p. 93.

[7] Zheng Y.J., Xiao F.X., Wang Y., Li C.H., Xu W., Jian H.S., Ma Y.T. Industrial experiment of copper electrolyte purification by copper arsenite. J. Cent. South Univ. Technol., 2008, 15(2): 204.

[8] Wang X.W., Chen Q.Y., Yin Z.L., Xiao L.S. Identification of arsenato antimonates in copper anode slimes. Hydrometallurgy, 2006, 84(3–4): 211.

[9] Wang X.W., Chen Q.Y., Yin Z.L., Wang M.Y., Tang F. The role of arsenic in the homogeneous precipitation of As, Sb and Bi impurities in copper electrolyte. Hydrometallurgy, 2011, 108(3–4): 199.

[10] Hua H.Q., Zhang Y. Study on arsenic existence from and practice of arsenic control during copper electrolysis. Min. Metall., 2011, 20(1): 68.

[11] Losilla E.R., Salvadó M.A., Aranda M.A.G., Cabeza A., Pertierra P., García-Granda S., Bruque S. Layered acid arsenates α-M(HAsO₄)₂·H₂O (M=Ti, Sn, Pb): synthesis optimization and crystal structures. J. Mol. Struct., 1998, 470(1–2): 93.

[12] Naïli H., Mhiri T. X-ray structural, vibrational and calorimetric studies of a new rubidium pentahydrogen arsenate RbH₅(AsO₄)₂. J. Alloys Compd., 2001, 315(1–2): 143.

[13] Qureshi M., Kumar V. Synthesis and IR, X-ray and ion-exchange studies of some amorphous and semicrystalline phases of titanium antimonate: separation of VO²⁺ from various metal ions. J. Chromatogr. A, 1971, 62(3): 431.

[14] Colomban Ph., Doremieux-Morin C., Piffard Y., Limage M.H., Novak A. Equilibrium between protonic species and conductivity mechanism in antimonic acid, H₂Sb₄O₁₁·nH₂O. J. Mol. Struct., 1989, 213, 83.

[15] Myneni S.C.B., Traina S.J., Waychunas G.A., Logan T.J. Experimental and theoretical vibrational spectroscopic evaluation of arsenate coordination in aqueous solutions, solids, and at mineral-water interfaces. Geochim. Cosmochim. Acta, 1998, 62(19–20): 3285.

[16] Zhao Z.S. Mechanism of arsenic removal in oxidized Fe-As system. Chin. Environ. Sci., 1995, 15(1): 18.

[17] T.B. Braun, J.R. Rawling, and K.J. Richards, Factors affecting the quality of electrorefined cathode copper, [in]_J.C. Yannopoulos and J.C. Agrwal, eds. International Symposium on Copper Extraction & Refining, Las Vegas, 1976, p. 511.

[18] Chen T.T., Dutrizac J.E. Mineralogical characterization of a copper anode and the anode slimes from the La Caridad copper refinery of Mexicana de Cobre. Metall. Mater. Trans. B, 2005, 36(2): 229.