Fundamental experiment of voloxidation off-gas treatment, (1)

In the reprocessing of FBR spent fuel for the voloxidation process (chopped spent fuel is oxidized and volatile fission products are released), the development of off-gas treatment system is important as well as that of the voloxidizer. Fundamental experiments have been carried out for the removal of tritium and iodine by molecular sieve adsorption; and the removal characteristics were made clear. (1) The molecular sieve adsorption method is effective for HTO collection, even in the existence of iodine. (2) For the micropores of MS-4A, the effect of iodine on H2O adsorption is negligible, and the retention of iodine is extremely small. (3) The iodine retention of MS-13X depends on the breakthrough of H2O. Its decontamination factor for iodine is satisfactory. (4) The simultaneous collection of iodine and HTO by MS-13X is possible. (5) Adsorption temperature and gas flow rate influence H2O adsorption characteristics, but do not affect the adsorption of coexisting iodine. (6) The desorption of iodine from MS-13X is influenced by H2O, although the desorption of H2O from a molecular sieve is not influenced by iodine. (J.P.N.)