结合体和固体相分隔铁酸盐,酸和铜共沉积物之间的结合体和固体相
Randi A Mendes1, Nefeli Bompoti1, Timothy M Vadas1
1Department of Civil and Environmental Engineering, University of Connecticut, Unit 3037, 261 Glenbrook Rd. Storrs, CT, 06269-3037, USA.
Chemosphere
|June 23, 2023
概括
这项研究揭示了氧化铁,酸和铜如何相互作用,影响铜的作用.
科学领域:
- 环境化学环境化学
- 地质化学 地质化学
- 生物地质化学生物地质化学
背景情况:
- 了解铁 (Fe) 氧化物,酸 (C) 和铜 (Cu) 之间的环境相互作用对于预测Cu命运至关重要.
- 目前在环境矩阵中测量这些元素的特定形式和化学相互作用方面存在局限性.
- 溶解和合体Cu度是Cu生物可用性和流动性的关键指标.
研究的目的:
- 为了研究pH的作用,Fe:C摩尔比率,以及Cu度对溶解和合体Cu的影响.
- 描述在吸附 (SOR) 和共沉降 (CPT) 反应过程中形成的体相.
- 评估模拟方法在预测Cu分区中的性能.
主要方法:
- 使用非对称流域流量分化 (AF4) 与总有机碳 (TOC) 分析和感应合等离子体质谱学 (ICP-MS) 相结合.
- 检查了pH (5-7) 和Fe:C分子比率 (1:0到1:3) 的范围内的反应.
- 应用了NICA-Donnan和ferrihydrite表面复杂化模型的添加性方法.
主要成果:
- 铁:C比率和pH值显著影响了溶解,体和固体相之间的Cu分区.
- 在pH 7时,Fe-C-Cu三元相包括~10%的溶解Cu;在pH 6时,只观察到Fe-Cu合物.
- 建模方法显示出差异,经常过度预测没有C的溶解Cu,并低于预测C的存在.
结论:
- 环境因素,如pH值和湿酸含量,极大地改变了Cu的分类和相位分布.
- 形成不同的体相 (Fe-C-Cu,Cu-C,Fe-Cu) 影响Cu的行为.
- 目前的模型需要改进,以便在复杂的环境系统中准确预测溶解和体的度.
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