2018 Fiscal Year Final Research Report
Redistribution of REE during transformation of ferrihydrite in natural groundwater
| Project/Area Number |
16K17836
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Petrology/Mineralogy/Economic geology
|
|---|
| Research Institution | Industrial Research Institute of Ishikawa |
|---|
Principal Investigator |
|
|---|
| Project Period (FY) |
2016-04-01 – 2019-03-31
|
| Keywords | フェリハイドライト / 希土類元素 |
|---|
| Outline of Final Research Achievements |
In the present study, (1) rare earth elements distribution between groundwater and colloids in deep granitic groundwater, (2) Sorption behavior of REE onto ferrihydrite, (3) Transformation experiments of ferrihydrite in natural groundwater were investigated. The results showed (1) Light REE enriched colloids were mobile in natural granitic groundwater. They affected REE patterns of the heavy REE enriched groundwater. (2) In laboratory experiments, almost all of the REE were sorbed around neutral pH. The REE surface complex possibly changed with pH. (3) Transformation of ferrihydrite in natural granitic groundwater were inhibited possibly by aqueous species.
|
| Free Research Field |
地球化学
|
| Academic Significance and Societal Importance of the Research Achievements |
現在まで、室内実験における準安定相の相転移挙動は水質条件(pHや酸化還元条件など)や相転移の妨害イオンの有無、微生物の活動などによって相転移プロセス・メカニズムが変化することが分かってきた。しかし、実際の天然の水質環境では、相転移挙動に影響を与える要因の複雑さから、天然環境に適応可能な統一的な解釈には至っていなかった。本研究で得られた成果により、天然環境において有害元素に対して高い吸着能を要する準安定鉱物の、地球表層環境における元素の移動におよぼす影響として、相転移の阻害現象が準安定鉱物の安定性に大きく影響している可能性が示唆された。
|
