MEASUREMENT OF RADIOACTIVE GASEOUS EFFLUENTS FROM VOLOXIDATION AND DISSOLUTION OF SPENT NUCLEAR FUEL.

Laboratory-scale tests gave data on the release of tritium, **1**4C, **8**5Kr, and **1**2**9I as radioactive gases from spent nuclear fuels during voloxidation and dissolution. Voloxidation, a proposed reprocessing step, is intended to remove tritium from fuel by oxidation of UO//2 to U//3O//8 prior to dissolution of the fuel with nitric acid. **1**4C, **8**5Kr, and **1**2**9I may be evolved in both steps. Quantitative data from the tests may be used in designing off-gas treatment processes and equipment. The tests were performed in a shielded cell with a combination voloxidizer-dissolver. With a recirculating off-gas system, tritium and **1**4C were trapped on molcecular sieves; **1**2**9I was trapped on silver-exchanged zeolite. **8**5Kr was measured by online gamma-ray counting. Zircaloy-clad UO//2 fuels from H. B. Robinson-2, Oconee-1, and Saxton reactors, with burnups from similar 100 to similar 28,000 MWD/MTHM, were tested.