Silver Recovery from X-ray Film Waste by Leaching and Precipitation Method Using Sodium Hydroxide and Sodium Sulfide

Abstract

Silver recovery study from X-ray film waste by leaching and precipitation method using NaOH and Na2S aims to determine the optimum conditions in silver recovery. The parameters optimated in this study were concentration of the precipitants, leaching temperature and effect of the type of precipitants on the precipitation time. The results showed that the NaOH and Na2S precipitants were able to recover silver optimally at the concentration of 1.5 M. The optimum leaching temperature of the film with the Na2S to recover silver was at 25oC, whereas in the NaOH the film leaching temperature only affected time of precipitation. Therefore, the formation of precipitate using Na2S was more efficient than NaOH, however the acquisition of silver was better in the use of NaOH than Na2S.