Silver Recovery Systems, Ion-Exchange Cartridge
Definition : Equipment designed to recover silver from solutions by substituting ions in the solution for other ions bound to a large polymer molecule. The silver solution is passed through a packed resin cartridge (or column), and then the resin releases its exchange ion for an ion of higher preference; in photographic (or x-ray) film processing, it can be the silver thiosulfate complex. Once the ion-exchange cartridge is exhausted, an acid solution (typically low-concentrated sulfuric acid) is sent through the resin, breaking down the silver thiosulfate complex that is held by the resin. A well-controlled system can remove silver to less than one part per million (ppm). Ion-exchange systems are used mainly in healthcare facilities to recover silver from solutions used during radiographic film processing. This technique is intended to treat dilute solutions like wash water; systems are usually used to achieve very low silver content in disposed water according to regulatory limits.
UMDC code : 17167