ネプテュニウムとアメリカシウムの特異化は,選択された玄武岩,花岩,シェール,タフの地下水に含まれています
Science (New York, N.Y.)
|July 15, 1983
まとめ
ネプテュニウムとアメリカシウムは,硫酸塩濃度が高い地下水,特に90°Cで溶解性が低い. 還元条件は,ネプチューニウムの降水をNp(IVとして好み,アメリシウムとキュリウムの溶解性に影響を及ぼします.
科学分野:
- 地質化学 地質化学
- 環境科学 環境科学
- 放射化学は放射化学である.
背景:
- ネプテュニウムとアメリカシウムは,核廃棄物処理で懸念される重要なアクチノイドである.
- 溶解性を理解することは,地質学的貯蔵庫における放射性核酸の移動を予測する上で極めて重要です.
研究 の 目的:
- ネプチューニウムとアメリカシウムの溶解性を高硫酸塩の地下水で高温で調べるために.
- これらのアクティニドの化学状態と溶解性を制限する相をシミュレートされたリポジトリ条件下で決定する.
主な方法:
- 溶解性実験は,硫酸塩濃度が高い合成地下水で90°Cで実施した.
- ネプチューニウムの特異性は,酸化還元電位測定と化学モデリングを使用して分析されました.
- 溶解度データを熱力学的予測と比較した.
主要な成果:
- ネプテュニウムとアメリカシウムは,試験された地下水条件において,溶解性が低いことを示した.
- ネプテュニウムの特異種は主にNp(IV) であり,溶解性が低かった.
- アメリシウムの溶解度 (Am(IIIとして存在する) は,キュリウムの溶解度と同等であることがわかりました.
結論:
- 高硫酸塩濃度と高温は,ネプトニウムとアメリカシウムの溶解性を制限する.
- 還元条件は,Np(IV) としてネプチューニウムの降水量を増加させると予想されています.
- これらの条件下でのアメリカシウムの溶解性行動はキュリウムと類似しており,三価アクチニドの行動に関する洞察を提供します.
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