Process and apparatus for the removal of silver from fixer solutions

摘要

An electrolytic process is used to reduce the silver content of fixer solution to a level such that it can be discharged as effluent. In the process silver is removed from aqueous fixer solutions by circulating the solution in a closed cycle through an electrolytic cell such that the residence time in the cell is not greater than one minute for each passage. The electrode loading is within the range between 5 and 15 mA/cm2 initially but is reduced in at least one further chronologically consecutive stage. Exhausted developer solution may be added to the fixer solution to act as a pH controlling redox system.