High purity gold is recovered from nitrate solution by nitrate decomposition to obtain a highly acidic solution from which gold is recovered by ferric ion addition

摘要

High purity gold recovery from nitrate solution involves nitrate decomposition and gold recovery from the resulting highly acidic solution by ferric ion addition. High purity gold is recovered from nitrate-containing precious metal solution by: (a) nitrate decomposition to obtain a solution with -4 mol/l H+ ion concentration; and (b) gold ion reduction by addition of an acidic Fe2+ solution having a -4 mol/l H+ ion concentration. Preferred Features: Step (a) is carried out using formic or ascorbic acid at 80-90 deg C, and step (b) is carried out under potential control at 60 deg C.