高性能自组装硫化纳米级零价值铁用于污染沉积物中的的固定:优化,微生物反应和机制
Yiqun Xu1, Hongdou Liu1, Siqi Wen1
1College of Environmental Science and Engineering, Yangzhou University, Yangzhou 225009, PR China.
Journal of hazardous materials
|March 14, 2024
概括
硫化纳米级零价值铁有效地固定污染沉积物中的,在各种环境条件下显示出高效率. 这种方法为沉积物修复提供了一个有前途的解决方案.
科学领域:
- 环境科学 环境科学
- 环境化学环境化学
- 材料科学 材料科学 材料科学
背景情况:
- 沉积物中的 (Cd) 污染对环境构成风险.
- 纳米级零价值铁 (nZVI) 显示了Cd修复的潜力,但其在复杂的沉积物环境中的有效性需要进一步研究.
- 硫化nZVI (S-nZVI) 已在水相中显示出高Cd去除,但其在沉积物中的性能和机制尚不清楚.
研究的目的:
- 研究与不同前体合成的S-nZVI在受污染的沉积物中固定的有效性.
- 评估S-nZVI对Cd物种化,生物可用性和沉积物中浸出的影响.
- 在各种环境条件下探索S-nZVI介导的Cd静止的稳定性和影响因素.
主要方法:
- 使用各种硫和铁前体合成S-nZVI.
- 合成的S-nZVI材料的特性 (形态,结晶性,氧化状态).
- 用Cd受污染的沉积物与最佳S-nZVI处理的化实验,评估Cd度,DTPA可提取的Cd,可交换的Cd和在90天内出.
- 在不同的pH值,水/沉积物比率,有机酸和共存离子下评估固定效率.
主要成果:
- 前体显著影响了S-nZVI形态,Fe(0) 结晶度和氧化程度.
- 使用Fe3+和S2-前体 (S/Fe = 0.14) 合成的S-nZVI实现了高达99.54%的Cd固定效率.
- 应用S-nZVI (1%和5%剂量) 显著降低了Cd在上层水和DTPA可提取/可交换Cd分数中的Cd (P <0.05).
- 在90天的时间里,在上面的水中观察到低Cd液和总铁.
- 在各种环境条件下 (pH,水/沉积物比,有机酸,共存离子) 保持了高Cd固定效率.
结论:
- S-nZVI 是一种高效的材料,可以在受污染的沉积物中固定.
- 选择前体对于优化S-nZVI性能至关重要.
- 碳酸固定是由沉积物特性,微生物群落以及碳酸的吸附,复杂化和沉驱动的.
- S-nZVI表现出强大的性能和稳定性,使其成为沉积物修复的有希望的技术.
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