Removal of sodium thiosulfate from wash water by the use of ion exchange resins for application in a closed photographic system

Ion exchange resins were used for removing sodium thiosulfate from wash water. Quantitative tests were run to determine the feasability of using the resins in a closed rapid processing system. One liter of a monobed resin and one liter of an anion resin, each in a separate ion exchange column, were found to be sufficient to remove the sodium thiosulfate left in the wash water for 8000 square inches of Kodabromide F-2 paper under specified conditions.