Screening test of adsorbents for recovery of krypton

A screening test of adsorbents was carried out in order to find out suitable adsorbents for the the removal of a radioactive noble gas (Kr-85) in the off-gas of nuclear reprocessing plants. The adsorption performances of various adsorbents for Kr were investigated at 195 and 273 K. The effect of nitrogen carrier gas on the adsorption of Kr was examined as well. Some carbon-based adsorbents-Ambersorb 572, Ryujyo-Sirasagi G2x4/6-3 and Molsievon X2M4/6-were found to have large adsorption capacities. The H-mordenite adsorbent fabricated from a natural mordenite by ion-exchange with the HCl solution was found to have a good adsorption performance for Kr, which is almost comparable to that of the activated charcoal.