Luženje polimetalnog Cu-Zn-Pb koncentrata natrijum-nitratom i sumpornom kiselinom

U radu su prikazani i diskutovani rezultati luženja polimetalnog sulfidnog Cu-Zn-Pb koncentrata rastvorom natrijum-nitrata i sumporne kiseline pri atmosferskom pritisku. Prikazan je hemijski i mineraloški sastav polaznog koncentrata i čvrstih ostataka nakon procesa luženja. Hemijske reakcije luženja i mogućnosti njihovog odvijanja analizirane su primenom termodinamičke analize na osnovu izračunatih Gibbsovih energija i analize E-pH dijagrama. Eksperimentalno je analiziran uticaj temperature i vremena na stepen izluženja korisnih metala iz sulfidnog koncentrata. Pokazano je da je moguće dobiti bakar, cink i železo u rastvoru u obliku sulfata, dok olovo u obliku anglesita (PbSO4) ostaje u čvrstom ostatku nakon procesa luženja. Železo se oksidiše u Fe (III) -sulfat, koji učestvuje u luženju sulfidnih minerala i prelazi u Fe (II) -sulfat.
The results of polymetallic sulphide Cu-Zn-Pb concentrate leaching with sulphuric acid in the presence of sodium nitrate as an oxidizing agent, at atmospheric pressure, are presented and discussed. Chemical composition and phase ratio of the starting concentrate and solid residuals after the leaching process are shown. Chemical reactions of leaching and their thermodynamic probabilities are predicted based on the calculated Gibbs energies and analysis of E-pH diagrams. The influence of temperature and time on the leaching degree of the concentrate's components is experimentally determined. It is shown that it is possible to obtain copper, zinc and iron in a solute form, while lead in the anglesite (PbSO4) form remains in the solid residual after the leaching process. The iron is being oxidized to Fe(III)-sulphate, which takes part in a sulphide leached minerals and turns into Fe(II)-sulphate.