The Chemical Behavior of Fission Product Iodine in Light Water Reactor Accidents

Thermochromatographic behavior of iodine in fused silica columns when evaporated from lead–bismuth eutectic

“…In a light-water reactor, iodine is assumed to occur in large part as CsI. This is a favorable outcome from a safety perspective as CsI is soluble in water as well as not very volatile [12]. There is however still a risk of aerosol formation, facilitating transport.…”

Technical considerations related to interim source-term assumptions for emergency planning and equipment qualification. [PWR; BWR]

“…Iodine chemistry is an important consideration in estimating iodine releases from a reactor during an accident, due to the large differences in behavior of different chemical forms of this element (Campbell, Malinauskas and Stratton, 1981;Parker and Creek, 1981;Morewitz, 1981;Wichner, Kress and Lorenz, 1981). Although many believe that the aqueous chemistry of iodine in reactors specifies cesium-iodine as the form of iodine present after release from fuel in the presence of water, the actual form at the instant of release from fuel is still deemed uncertain by some (Wichner, Kress and Lorenz, 1981;.…”

“…Before reactor vessel failure in an accident, when the core is heating to melting temperatures, H2 produced by a steam/zirconium reaction creates a reducing environment will exist in most, if not all, accidents B-18 as a result of the interaction of the coolant with the cladding at high temperatures (Campbell, Malinauskas and Stratton, 1981;Parker and Creek, 1981). Therefore, many of the fission product species may exist in a reduced state rather than that predicted in air or at higher oxygen pressures.…”

Study of the radiolytic decomposition of CsI and CdI2 aerosols deposited on stainless steel, quartz and Epoxy painted surfaces

“…In the RCS, Iodine and Caesium have been assumed for several decades to be bounded (CsI species) [23]. In fact, from thermodynamic calculations [24,25,26], experiments [27] and the ratio between Cs and I masses transported in different kinds of RCS experiments [28, 29,30], it has been assumed that CsI could be the main aerosols species entering into the containment [31,32,33]. CdE aerosol has also been identified [34,35,36] and its importance has been assessed in more recent studies [37,38,39].…”