Abstract:
For complex desorption gold mud with high silver and copper content,a combined process of FeCl3 acid leaching-silver anode casting-silver electrolysis for gold and silver separation was studied.The optimum conditions were obtained through the experiment,that the dosage of FeCl3 expressed as n(Fe3+)/n(Cu) is 2.8,HCl concentration is 2.5 mol/L,liquid-solid ratio is 4∶1,the reaction temperature is 80 ℃,the reaction time is 2.5 h.Under these conditions,the leaching rates of Cu,Pb and Fe were 97.25 %,98.24 % and 99.67 % respectively,and the leaching rates of Au and Ag were only 0.027 % and 0.441 % respectively.The purpose of separating noble and base metals effectively was achieved.The gold mud was cast into silver anode plate after removing impurities,and the main metal mass fraction were Au 21.47 %,Ag 78.59 %,Cu 0.89 % and Pb 0.04 %.This anode plate was easily purified by silver electrolysis to get Ag-Ⅰand Au-Ⅰ.It is an ideal process to treat desorption gold mud with high silver and copper content.