Recovery of gold and silver from copper anode slime

This study has shown that gold and silver can be recovered from a complex anode slime containing copper, selenium, and tellurium, but a carefully planned leaching procedure is required. To extract the gold with thiourea, it is necessary to first remove the copper, selenium, tellurium, and most of the silver from the mixture. Once these elements are removed, the gold and most of the remaining silver can be extracted in high yields by leaching with thiourea solutions. It is possible to collect the gold and silver (as well as copper, selenium, and tellurium) in separate phases where they can be purified more easily. No additional step is necessary to separate the silver and gold from each other.