Method for recovering silver from photographic processing solution

摘要

There is disclosed a method for recovering silver from photographic processing solution by electrolysis, in which method the cathode potential is set at a potential range wherein a precipitate of silver sulfide is formed in the electrolytic cell. According to the method, intensive silver recovering leading to low concentration of residual silver in the solution is achieved. Structure of electrolytic apparatus enabling easy separation of silver sulfide precipitates is also disclosed. Application of lead peroxide to the material of anode improves the life of the anode. Further advantages of the method are remarkable decreases in COD and iron contents of waste solution.