THIOSULFATE LEACHING OF SILVER FROM A SOLID RESIDUE AFTER THE PRESSURE LEACHING OF LUBIN (KGHM) CONCENTRATE
More details
Hide details
1
Wroclaw University of Technology
2
Wrocław University Of Technology
Publication date: 2015-02-20
Corresponding author
Krzysztof Gibas
Wrocław University Of Technology, wyb. Stanisława Wyspiańskiego 27, 50-370 Wrocław, Poland
Physicochem. Probl. Miner. Process. 2015;51(2):601-610
KEYWORDS
TOPICS
ABSTRACT
The possibility of hydrometallurgical recovering of silver from a solid residue after pressure leaching of the flotation copper concentrate from Lubin Concentrator (KGHM) has been investi-gated. The thiosulphate leaching was examined with regard to the highest possible leaching effi-ciency and optimization the process parameters. The effect of thiosulfate ions concentration within the range from 0.25 to 1.00 mol/dm3 at a constant ammonia concentration, and effect of ammonia concentration within the range from 0.40 to 1.00 mol/dm3 at a constant thiosulfate concentration on the leaching recovery of selected metals were examined. Moreover, the effect of copper(II) ions addition on the silver leaching process was studied. It was shown that the leaching recovery of silver increases with increasing thiosulfate and ammonia concentration. At the highest thiosulfate ions concentration, the observed silver leaching recovery was 60%. The best results were obtained at ammonia concentration of 0.80 mol/dm3, where Ag leaching recov-ery reached 75%. The results for Cu(II) ions addition effect on the recovery of silver(I) ions showed, that Cu(II) addition does not affect silver concentration during leaching process. There-fore, Cu(II) presence is unnecessary in this process. Nearly 100% efficiency of the thioslulohate silver leaching was achieved by pretreatment of the solid residue after pressure leaching with NaOH solutions.