Interactions of I2 and CH3I with reactive metals under BWR severe-accident conditions

Journal article, 2004

I-2 released from fuel in the event of a severe nuclear reactor accident has the ability to deposit on surfaces in the containment building. This study has focused on the reactions of I-2 with reactive metals available in the containment. The experiments have been performed under conditions similar to those in a boiling water reactor at an accident situation. Copper, zinc and aluminium showed extensive uptake of gaseous I-2 under humid conditions. Reaction rates were determined at 25, 50 and 70degreesC and could be used for quantifying the effect of reactions between gaseous I-2 and copper, zinc and aluminium. Experiments with the metals placed in water showed lower I-2 uptake. Zinc iodide and aluminium iodide rapidly dissolves in water and no uptake of I-2 on these surfaces could be verified. Copper iodide has low solubility and I-2 was adsorbed on the surface. Experiments performed with reactive metals and methyl iodide showed a minor uptake of methyl iodide on zinc and aluminium in the gas phase for temperatures up to 80degreesC. A continuous uptake of methyl iodide on copper was measured at 80degreesC.