Treatment of fuel debris by selective fluorination and molten salt electrolysis

2014 Fiscal Year Final Research Report

• Project/Area Number: 25630429
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Nuclear engineering
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: MATSUURA Haruaki 東京工業大学, 原子炉工学研究所, 助教 (70262326)
• Co-Investigator(Renkei-kenkyūsha): SATO Nobuaki 東北大学, 多元物質科学研究所, 教授 (70154078)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 燃料デブリ / 選択フッ化 / 溶融塩電解 / 酸化ウラン / 酸化ジルコニウム / 固溶体

Outline of Final Research Achievements

For stabilization of fuel debris at Fukushima Daiichi power plant accident, basic experiments of selective fluorination and molten salt electrolysis have been performed. To separate between uranium and zirconium without vaporization of uranium by fluorination, solid solution should be fluorinated by hydrogen fluoride gas at less than 400 oC, so that uranium would be selectively fluorinated into uranium tetrafluoride. And then, uranium can be dissolved into molten fluoride salt and electroreduced by electrolysis. To avoid fluorination of zirconium, pre-treatment of hydrogen reduction is not suitable. Even pre-treatment of oxidation would be effective to avoid zirconium fluoride vaporization at higher temperature.

Free Research Field

溶融塩物理化学