Radon capture with silver exchanged zeolites

摘要

To enable laboratory work with larger amounts of ~(226)Ra and its decay products, e.g., ~(222)Rn and its daughters, these need to be captured in order to avoid unnecessary alpha contamination of the laboratory work space and ventilation systems.In this study, radon gas was pumped through a column filled with the silver exchanged zeolite called "silver ex-changed molecular sieves 13X" (Ag_(84)Na_2[RAl_O2)_(86)(SiO_2)_(106)]. xH_2O). After exposure to radon, the radioactivity of the zeolite was measured repeatedly using high resolution gamma spectrometry. It was shown that radon was captured and retained in the silver exchanged zeolite. The zeolites' ability to retain radon was decreased by formation of metallic silver, caused by ionizing radiation. However, the zeolite was regenerated by heating and its radon capture ability was restored. The daughters of radon are not in gas phase and will hence stay on the column.