Estimation of TEDA Filtration Effectiveness for Different Chemical Forms of Radioactive Iodine

Would probably emerge to the environment at severe nuclear power plant accident. It is important to understand and analyze Iodine behavior because it is one of the large contributors to the effective dose in this kind of events.

Several mechanisms determine the composition of Iodine released (in terms of chemical composition) to the environment. Most iodine will be emitted in the form of Cesium Iodide (Csl), some of it emitted in the form of aerosols. In addition, depending on the environment conditions, the iodine (I) can compose with itself and with the materials surrounding it (i.e. water and organic compounds) to form different kinds of substances, referred here as elemental Iodine (I₂, I) and organic Iodine (CH₃I) (1).

In order to protect Inhalation against iodine isotopes, there are several kinds of filters. Each kind of filter got its own adsorption characteristics. One of the most common filters is TEDA (Triethylene di-amine) filter. This filter is considered as a good protective filter against small molecular structure materials such as radioactive Iodine (2) (3).

This work, is suggesting a way to estimate the efficiency of filtration manners regarding to the different forms of Iodine (elemental, aerosol and organic). First results are showing that the diatomic iodine (I₂) can be easily protected by thick cloth, while the capture of organic iodides compounds is less effective in those manners. There is also humidity and filter temperature dependence (2) (3).

References

Clement, L. Cantrel, G. Ducros, F. Funke, L. Herranz, A. Rydl, G. Weber,C. Wren State of the art report on Iodine chemistry, Nuclear energy agency committee on the safety of nuclear installation, 2007. 2. J.F. Wang, T. Kobayashi, Y. Uzuyama, K. Endo, Development of organic Iodine adsorbents, Rasa industries Ltd, Japan, TopSafe, 2017. 3. Hoo Kun Lee and Geun II Park, Adsorption characteristics of elemental iodine and methyl iodide on base and TEDA impregnated carbon, Korea atomic energy research institute, 1995.