Radiolysis of cesium iodide solutions in conditions related to those prevailing in a pressurized water reactor after severe core damage

Measurements were made of I2 and IO3- formed when aqueous CsI solutions were exposed to two temperatures 430 and 950C with irradiation. Parameters varied were time, dose, CsI concentration, boric acid concentration, Cs2 CO3 concentration, in the presence of air, air-carbon dioxide, and air-carbon dioxide-hydrogen mixtures, to provide information for calculation of the form in which iodine released from fuel as CsI in a reactor accident might reach the environment. In some experiments a two-compartment cell was used in order to trap the gaseous iodine produced. In this case it was found that the quantity of gaseous iodine produced increased roughly linearly with the dose (at the dose rate used). In addition it was found that IO3- is radiolyzed into I- and I2. (author)