The results of our assessment of the processing methods and costs for the recovery of cesium, techneium, rhodium, and palladium from aged waste supernates are presented. Guidelines for the assessment of costs are given. Cesium can be readily absorbed from alkaline waste supernates without prior treatment using Linde AW-500, a synthetic zolite. Technetium, present in the supernate as the pertechnetate anion, together with rhodium and palladium, probably present as anionic nitrite complexes, can be absorbed from untreated waste supernates using Dowex 1-X4 or similar anion resins. Although the behavior of cesium and technetium is reasonably well understood, the behavior of the anionic complex that accounts for the presence of rhodium and palladium in this strongly alkaline solution is not well understood. Further work is required before a process can be outlined for the clean separation of rhodium and palladium from the technetium-rhodium-palladium crude fraction sorbed on the anion resin. An assessment of capital and operating costs for the recovery of cesium only, technetium only, or both cesium and technetium are tabulated. No costs are shown for rhodium and palladium, since the technology for their separation is not sufficiently advanced. However, the incremental cost for their separation from technetium is expected to be small. Process flow diagrams for the recovery of cesium and technetium by ion exchange are shown.
