2000 Fiscal Year Final Research Report Summary
Geochemical analyses on long-term performance of engineered barrier
| Project/Area Number |
09308013
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A).
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
エネルギー学一般・原子力学
|
|---|
| Research Institution | THE UNIVERSITY OF TOKYO |
|---|
Principal Investigator |
SUZUKI Atsuyuki The Univ.of Tokyo, School of Engineering, Professor, 大学院・工学系研究科, 教授 (50011135)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OMORI Ryota The Univ.of Tokyo, School of Engineering, Lecturer, 大学院・工学系研究科, 講師 (10262049)
NAGASAKI Shinya The Univ.of Tokyo, Graduate School of Frontier Science, Associate Professor, 大学院・新領域創成科学研究科, 助教授 (20240723)
TANAKA Satoru The Univ.of Tokyo, School of Engineering, Professor, 大学院・工学系研究科, 教授 (10114547)
TODORIKI Masaru The Univ.of Tokyo, School of Engineering, Research Associate, 大学院・工学系研究科, 助手 (10270886)
|
|---|
| Project Period (FY) |
1997 – 2000
|
| Keywords | engineered barrier / Bentonite / sorption / Smectite / Neptunium / hydrotalcite / 収着 / ヨウ青酸イオン |
|---|
| Research Abstract |
For the improvement of safety assessment of radioactive waste disposal, it is important to install the material that has high capacity to sorb IO_3^-. Hydrotalcite-like compound, of which CO_3^<2->, NO_3^- or Cl^- etc. is contained in its interlayer, is considered to be a potential clay mineral for sorbing IO_3^-. In the present study, we studied the sorption behavior of IO_3^- to CO_3^<2->-hydrotalcite (HTCO_3) that contains CO_3^- as interlayer anion and NO_3^--hydrotalcite (HTNO_3) that contains NO_3^- as interlayer anion in order to understand the difference of the sorption mechanism of IO_3^- to the different type of hydrotalcite. It was found that the time to reach sorption equilibrium was shorter for HTCO_3 than that for HTNO_3, that the sorption isotherm for HTCO_3 consisted of two Langmiur type sorption processes but that for HTNO_3 consisted of one, and that the desorption behavior was quite different each other. These results suggest that the sorption of IO_3^- is occurred weakly on the external surface of HTCO_3 and includes two mechanisms of sorption. On the other hand, the sorption of IO_3^- to HTNO_3 is occurred in its interlayer by the anion exchange reaction. Furthermore, the sorption mechanisms of IO_3^- to HTCO_3 and HTNO_3 were also discussed from DTA/TG and Powder-XRD measurement.
|
