Chemical composition of artificial seawater after leaching tests of irradiated fuel

Tanaka, Kosuke; Suto, Mitsuo; Onishi, Takashi; Akutsu, Yoko; Yoshitake, Tsunemitsu; Yamashita, Shinichiro; Sekioka, Ken*; Ishigamori, Toshio*; Obayashi, Hiroshi; Koyama, Shinichi

JAEA-Research 2013-036, 31 Pages, 2013/12

JAEA-Research-2013-036.pdf:3.31MB

In the accident of Fukushima Daiichi NPPs, the water ingress was performed in order to decrease the reactor temperature. At that time, sea water was temporarily used as a coolant and the water contacted with nuclear fuel directly. It can be supposed that fission products (FP) were easily migrated from the fuel to sea water in this situation and that affect the water quality. The knowledge of leaching behavior, therefore, is necessary for evaluating the integrity of reactor component materials such as steels for pressure containment vessel and for reactor vessel. In order to obtain the fundamental knowledge for leaching behavior of FP in the hot sea water, the leaching tests of irradiated fuel were performed and the leachates were subjected to chemical analysis. It is found that he leaching rate of each nuclides obtained in this study were similar to that of the leaching results simulating the underground water.

Reformation of hazardous wastes into useful supporting materials for fast reactor fuels

Osaka, Masahiko; Miwa, Shuhei; Tanaka, Kosuke; Akutsu, Yoko; Ikeda, Kaoru*; Mimura, Hitoshi*; Suzuki, Tatsuya*; Usuki, Toshiyuki; Yano, Toyohiko*

Annals of Nuclear Energy, 38(12), p.2661 - 2666, 2011/10

https://doi.org/10.1016/j.anucene.2011.07.030

Novel concepts for effective utilization of molybdenum (Mo) from nuclear waste and magnesium silicates from hazardous asbestos wastes are proposed. A fast reactor cycle scheme that incorporates each material is described in the present paper. Basic studies on some fundamental technologies for the present cycle are given. Basic separation aspects for Mo by using LIX63 micro capsules and tertiary pyridine resin were investigated. A simple chemical synthesis route for Mo precursor powder from Mo containing HNO solution was tested. Effects of impurities in recovered Mo on sintering behavior were experimentally investigated.

Nitric acid dissolution test of simulated molybdenum CERMET fuels

Akutsu, Yoko; Osaka, Masahiko; Obayashi, Hiroshi; Yoshimochi, Hiroshi; Onose, Shoji

no journal, , 

Research and development of Mo-cermet fuel for fast reactors are underway. The purpose of this study is to investigate the dissolution behavior of Mo-cermet fuel in wet reprocessing. Several molybdenum compounds having different compositions that simulat Mo-CERMET fuel were prepared. Dissolution tests on these compounds were carried out. Dissolution behavior such as dissolution rates of the compounds were evaluated.

Development of selective separation method of nuclear rare metal by highly-functional xerogel, 1; Separation of platinum groups

Onishi, Takashi; Akutsu, Yoko; Obayashi, Hiroshi; Koyama, Shinichi; Ishigamori, Toshio*; Sekioka, Ken*; Mimura, Hitoshi*; Kawamura, Takuya*; Sugai, Hiroshi*

no journal, , 

As part of a development of nuclides separation process by using highly-functional xerogels, xerogels including insoluble ferrocyanide compounds were prepared for separation of Pt group metals. Adsorption and elution behaviors of Pt group metals were investigated in simulated high level radioactive liquid waste.

Effect of impurity on sintering and dissolution behavior of simulated molybdenum cermet fuels

Akutsu, Yoko; Tanaka, Kosuke; Osaka, Masahiko

no journal, , 

I studied the new fuel for fast reactors which assumed molybdenum an inert matrix. The purpose of this study is to grasp the dissolution behavior in wet reprocessing. Therefore I produced a molybdenum compound of various kinds of composition that simulated Mo CERMET fuel. I carried out a examination using this and evaluated the characteristics such as sintering and dissolution rates.