Carbon, fixed forms radioactive

Also for separation of radioactive matter from nuclear power plants activated carbons are used [11,41]. Activated carbon filters are applied to prevent the release of radioactive iodine (in elemental form and as methyl iodide) and noble gases such as krypton and xenon into the atmosphere. Filter units of that kind are used to adsorb accidental leakages of radioactive gases and vapours. Activated carbons are usually impregnated with potassium iodide or triethylenediamine. Nuclear-grade carbon adsorbents are narrow-pored (highly microporous) and a process consists of a fixed bed. 

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