Recovery of silver from industrial wastes, cassava solution effects

In this work, silver was recovered from X-ray films by dissolving the silver compounds with concentrated nitric acid. Internal electrolysis and external electrolysis methods were carried out using a steel electrode as cathode and a copper electrode as anode. Similarly, internal electrolysis and external electrolysis were carried out by adding cassava-derived cyanide solution. The results of recovery by internal and external electrolysis were compared. Addition of cassava-derived cyanide solution proved to give a better recovery in both methods. The results showed that external electrolysis also gave a better recovery. However, on the basis of energy consumption, silver recovery by internal electrolysis with cassava-derived cyanide solution is recommended for both solid and effluent wastes from industries. (C) 2000 Elsevier Science B.V. All rights reserved.