亚纳米级FeOOH集群通过铁改性生物炭在土水系统中驱动固定和甲基化抑制
1Fujian Provincial Key Laboratory of Ecology-Toxicological Effects & Control for Emerging Contaminants, Key Laboratory of Ecological Environment and Information Atlas, College of Environmental and Biological Engineering, Putian University, Putian 351100, China.
Water research
|July 20, 2025
概括
用铁修饰的生物炭 (Fe-BC) 通过形成稳定的复合物,有效地使 (Hg) 在土中停滞不前,显著减少有毒甲基 (MeHg) 的产生和生物可用性. 这种方法为污染提供了可持续的解决方案.
科学领域:
- 环境科学 环境科学
- 土壤化学 土壤化学
- 材料科学 材料科学 材料科学
背景情况:
- 在系统中的 (Hg) 污染是一个主要的环境和健康问题.
- 微生物甲基化将无机Hg转化为高度有毒的甲基 (MeHg).
- 生物炭 (BC) 显示重金属修复的潜力,但其Hg固定能力是有限的.
研究的目的:
- 阐明铁修饰生物炭 (Fe-BC) 在稳定Hg和抑制米系统中MeHg形成的分子机制.
- 研究Fe集群结构和大小对Hg吸附的作用.
- 了解共存的土壤离子对Fe-BC的Hg吸附的影响.
主要方法:
- 进行了批量实验,以评估Hg吸附和MeHg形成.
- 密度函数理论 (DFT) 的计算被用来探索分子相互作用.
- 研究了 FeOOH 集群在 BC 上的大小依赖性表现.
主要成果:
- Fe修饰通过协调FeOOH集群与BC表面组来增强Hg亲和力.
- FeOOH二极管 (FeOOH) 2表现出最强的结合能力和最高的Hg固定能力.
- 通过加强Hg吸附,Fe-BC显著降低了MeHg的产生和生物可用性.
- 同时存在的离子 (Na+,Cl-,SO42-) 调节了Hg吸附,Cl-和SO42-促进了稳定的复合体形成.
结论:
- Fe-BC,特别是像 (FeOOH) 2这样的亚纳米级FeOOH集群,有效地固定了在米土壤中的Hg.
- 优化Fe集群结构和了解离子相互作用对于最大限度地提高修复效率至关重要.
- 这项研究为基于Fe-BC的整治策略提供了分子洞察力和实际指导.
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