Mechanism of precipitate removal of arsenic and bismuth impurities from copper electrolyte by antimony

摘要

This paper aims to discover the mechanism of removal of arsenic and bismuth from copper electrolyte under the function of antimony. The precipitate was obtained from a synthetic copper electrolyte containing 185g/L sulfuric acid, 45g/LCu~(2+), 10g/LAs, 0.5g/LBi and 1.2g/LSb. The structure, morphology and component of the precipitate are clarified by methods of chemical analysis, SEM, XRD, TEM and IR spectroscopy. The precipitate consists of 27.08% arsenic, 15.12% antimony, 12.08% bismuth. There are many irregular blocks, and dendritic particles on the surface. The characteristic bands in the IR spectra of the precipitate are O-H, As-OH, As-O, As-OX (X=As, Sb, Bi), Sb-OH and O-As-O. The precipitate is a mixture of microcrystalline of BiSb_2O_7, Bi_(12)As_2O_(23), SbASO_4 and (Sb, As)_2O_3 by XRD and electronic diffraction. The impurities of As, Sb and Bi are removed from copper electrolyte by antimony attributing to these precipitate.