Iodine-Metal Surface Interactions under Severe Accident Conditions in a Nuclear Power Plant
Doctoral thesis, 2005

In the event of a severe nuclear reactor accident, iodine will be released from the fuel and eventually enter the containment. Radioactive iodine isotopes constitute both an acute and a long-term threat to humans, owing to its half-life and its accumulation in the thyroid gland. To produce reliable models predicting the possible environmental exposure, it is crucial to consider the chemical reactions involving iodine in the containment. This work has been an effort to extend the knowledge of iodine chemistry during severe accidents by studying reactions between iodine and reactive metals present in the containment, metals that have as yet been little studied. In addition, the influence of radiation on iodine-metal interactions and the formation of iodine radiolysis products in the gas phase have been studied experimentally. Reactions between I2, CH3I and three metals (Cu, Zn and Al) were studied in a humid nitrogen atmosphere. I2 had a great affinity for all three metals, and adsorption rates as well as activation energies for the reactions could be determined. CH3I had an affinity only for Cu above 50ºC, and the adsorption rate was then several orders of magnitude lower than in the I2 case. Surface analysis showed that I2 and CH3I were chemisorbed as metal iodide. I2 was also retained on Cu in acidic solutions, with an adsorption rate about two orders of magnitude lower than the gas phase reactions. I2 was converted to I- on Al and Zn surfaces in acidic solutions. Conversion rate constants were determined for temperatures up to 140ºC. Mass spectrometry methods failed to identify iodine species formed through radiolysis reactions in air or nitrogen.


reactive metals





10.15 KB-salen
Opponent: Professor, Reinhardt Odoj, Forschungszentrum Jülich, Germany


Henrik Glänneskog

Chalmers, Chemical and Biological Engineering

Apparatus for on-line measurements of iodine species concentration in aqueous and gaseous phases

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,; Vol. 498(2003)p. 517-521

Journal article

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

Nuclear Engineering and Design,; Vol. 227(2004)p. 323-329

Journal article

Subject Categories

Civil Engineering

Chemical Sciences



Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 2374

10.15 KB-salen

Opponent: Professor, Reinhardt Odoj, Forschungszentrum Jülich, Germany

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