Electro-Recovery of Gold (III) from Aqueous Solutions and Refractory, Boulangerite (Pb5Sb4S11) Ore
Afzal Shaha, b, c*, Sirajuddinb, d, Abdul Niazb, M. I. Bhangerb, M. K. Jamalib
a Kohat University of Science and Technology, Kohat (NWFP), Pakistan
b National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro (76080) Pakistan
c School of Chemistry, university of Wales Bangor, Gwynedd LL57 2UW, UK
d School of Chemistry, Clayton Campus, Monash University, Melbourne, Vic 3800, Australia
E-mail: afzalnm@yahoo.com

A very simple cell containing two stainless steel static sheet electrodes has been employed for electrolytic recovery of gold from a stirred aqueous solution containing 50 ppm Au. Cell potential, pH, stirring, temperature, time of electrolysis and addition of ammonia have been studied as the main parameters for optimization. The results show that the maximum deposition of 99.6% gold occurs at a cell potential of 2.8 V, pH 6.4, temperature 40 C in an optimum electrolysis time of only 60 minutes. The method was successfully applied to a refractory gold ore with an average gold recovery of 95.1%.

Keywords: Gold, electrolytic recovery, ammonia, boulangerite ore.