# Nuclear Science and Techniques

《核技术》(英文版) ISSN 1001-8042 CN 31-1559/TL     2019 Impact factor 1.556

Nuclear Science and Techniques ›› 2015, Vol. 26 ›› Issue (1): S10311

### Numerical analysis on element creation by nuclear transmutation of fission products

Atsunori Terashima1,  and Masaki Ozawa2

1. 1Department of Nuclear Engineering, Graduate School of Science and Engineering,
Tokyo Institute of Technology, 2-12-1-N1-21 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
2Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology,
2-12-1-N1-21 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
• Contact: Atsunori Terashima E-mail:terashima.a.aa@m.titech.ac.jp
Atsunori Terashima, and Masaki Ozawa. Numerical analysis on element creation by nuclear transmutation of fission products.Nuclear Science and Techniques, 2015, 26(1): S10311

Abstract:

A burnup calculation was performed to analyze the Apr`es ORIENT process, which aims to create highlyvaluable
elements from fission products separated from spent nuclear fuels. The basic idea is to use nuclear
transmutation induced by a neutron capture reaction followed by a ?? decay, thus changing the atomic number
Z of a target element in fission products by 1 unit. LWR (PWR) and FBR (MONJU) were considered as the
transmutation devices. High rates of creation were obtained in some cases of platinum group metals (44Ru
by FBR, 46Pd by LWR) and rare earth (64Gd by LWR, 66Dy by FBR). Therefore, systems based on LWR and
FBR have their own advantages depending on target elements. Furthermore, it was found that creation rates of
even Z0 (= Z + 1) elements from odd Z ones were higher than the opposite cases. This creation rate of an
element was interpreted in terms of “average 1-group neutron capture cross section of the corresponding target
element hcZi00 defined in this work. General trends of the creation rate of an even (odd) Z0 element from the
corresponding odd (even) Z one were found to be proportional to the 0.78th (0.63th) power of hcZi, however
with noticeable dispersion. The difference in the powers in the above analysis was explained by the difference
in the number of stable isotopes caused by the even-odd effect of Z.