Americium isotopes generated in the MOX fuel irradiated in the experimental fast reactor JOYO were analyzed by applying a sophisticated radiochemical technique. Americium was isolated from the irradiated MOX fuel by a combined method of anion-exchange chromatography and oxidation of Am. The isotopic ratios of americium and its content were determined by thermal ionization mass spectroscopy and α-spectrometry, respectively. The americium isotopic ratio was similar for all the specimens, but was significantly different from that of PWR-MOX. On the basis of present analytical results, the accumulation and transmutation behavior of americium nuclides in a fast reactor is discussed from the viewpoints of neutron spectrum dependence and the isomeric ratio of the241Am capture reaction. The estimated isomeric ratio is about 87%, which is close to the latest evaluated value. A rapid estimation method of Am content by using the240Pu to239Pu ratio was adopted and proved to be valid for the spent fuel irradiated in the fast reactor. © 2005 Elsevier Ltd. All rights reserved.
Osaka, M., Koyama, S. I., Maeda, S., & Mitsugashira, T. (2005, May). An experimental investigation of accumulation and transmutation behavior of americium in the MOX fuel irradiated in a fast reactor. Annals of Nuclear Energy. https://doi.org/10.1016/j.anucene.2004.12.009