in: Recycling Technologies for Secondary Zn-Pb Resources, Muammer Kaya, Editor, Springer, London/Berlin , New York, pp.291-348, 2023
Different processing techniques are practised to treat the inorganic (such as H2SO4) or inorganic acid (such as citric or malic acid) leached Pb–Zn oxide ores/wastes to recover the remaining Pb as well as Ag with a high Fe content in the first stage leach residues. These wastes may come from the Waelz process, mine/ mineral processing tailings, etc. Brine solutions (NaCl and CaCl2), alkaline solutions (NaOH), organic acids (malic, acetic, and oxalic acids), urea, and potassium sodium tartrate were tested alone or combined leaching (such as H2SO4 + NaCl; H2SO4 + FeCl3.6H2O), citric acid + NaNO3; acetic acid + Na-citrate, and citric acid + Na-citrate) were also performed. Chloride leaching is the most recognized and widely used Pb recovery method. Chloride leaching processes have been employed using either NaCl, MgCl2 and CaCl2, or FeCl3 along with HCl. NaOH + potassium sodium tartrate was found the best lixiviant for Pb leaching from Turkish oxidized Pb–Zn oxidized flotation tailings.