稀土元素与铁有机物合物相互作用作为REE环境传播的控制
Yasaman Tadayon1, Delphine Vantelon2, Julien Gigault3
1Univ. Rennes, CNRS, Géosciences Rennes, UMR 6118, F-35000 Rennes, France.
Journal of colloid and interface science
|November 5, 2023
概括
稀土元素 (REEs) 主要与铁有机物合物中的有机物结合. 它们的移动性取决于pH值,较小的合物控制pH值6的REE行为,pH值4的聚合物固定REE.
科学领域:
- 环境化学环境化学
- 地质化学 地质化学
- 体科学 体科学 体科学
背景情况:
- 稀土元素 (REEs) 对先进技术至关重要,引发了环境问题.
- REE的移动性受到与固体表面,特别是合体的结合的影响.
- 由于REE的存在和气候变化影响,铁有机物 (Fe-OM) 合物越来越多地被研究.
研究的目的:
- 研究pH对REE结合和Fe-OM合体内移动性的影响.
- 了解Fe-OM合体的结构修改如何影响REE行为.
- 澄清 colloids 在控制 REE 规范和环境命运中的作用.
主要方法:
- 研究了REE与有机物 (OM) 和Fe-OM合物的铁 (Fe) 组成部分的结合.
- 研究了pH (特别是pH6和pH4) 对合体结构和REE关联的影响.
- 分析了有机合物 (<3 kDa) 的溶解和Fe-OM聚合.
主要成果:
- REEs主要与Fe-OM合物中的OM分数结合.
- 在pH6下,小型有机合物 (<3kDa) 的溶解决定了REE的物种化和流动性.
- 在pH 4时,Fe-OM合物聚合,减少REE结合,但可能会使那些通过沉积结合的合物不动.
结论:
- 体在控制REE在环境中的物种化和传播方面发挥着至关重要的作用.
- 了解pH依赖的合体行为对于评估REE命运和生态毒理学至关重要.
- 这些发现与预测REE在环境条件变化和度增加的情况下的行为有关.
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