The Behavior of Zinc, Copper, and Indium During the Precipitation of Lead Jarosite

The behavior of zinc (Zn), copper (Cu), and indium (In) during the precipitation of lead jarosite (Pb-J) was investigated. At a temperature of 150°C and sulfuric acid concentration of 20 g/L, increasing concentrations of Zn, Cu, and In in the solution facilitated the formation of lead jarosite in the solid product. However, the incorporation of Zn remained consistently low, with less than 3% Zn present in precipitates from solutions containing ~ 150 g/L Zn. Mass balance calculations indicated that less than 1.2% of Zn precipitated into the solid products under all experimental conditions. The precipitation of Cu decreased with increasing concentration, while ~ 25% of In precipitated and remained stable across different concentrations. The order of substitution into Pb-J was approximately: In > Cu > Zn. The incorporation of Zn, Cu, and In influenced the morphology of the solid products, with Cu and In exhibiting similar morphologies. Additionally, PbSO₄ was encapsulated within the jarosite structure, resulting in the distribution of Zn, Cu, and In between PbSO₄ and Pb-J phases, predominantly within Pb-J.