Leaching rates for cesium, strontium, cerium, and aluminum from amorphous alumina calcine produced in the Waste Calcining Facility of the Idaho Chemical Processing Plant have been determined. Each gram of the calcine contained 26 mCi of cerium-l44, 10.5 mCi of cesium-137, 7.6 mCi of strontium-90, 1.4mCi of ruthenium~106, and lesser amounts of other fission products. Rates were obtained for cesium, strontium, and aluminum with distilled water at 25°C and 80 to 90°C and with di¬lute nitric acid (0.25 to 0.5M) at 25°C. In distilled water, the leaching rates for cesium and strontium were two to three orders of magnitude higher than the rates for aluminum, while the leaching rates for cerium and ruthenium were apparently the same as the leaching rate for aluminum. The leaching rate for aluminum at 80 to 90°C was 2 to 3 times higher than the rate at 25°C, but the aluminum leached was still less than 0.03 percent in 7 weeks. The amount of calcine dissolved in water is relatively low;therefore, the high leaching rates of cesium and strontium makes recovery of these fission products from WCF calcine potentially feasible.
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