使用硫化和未涂层的零价值铁 (ZVI) 在受污染的无氧含水层沉积物中固定
Thiago Augusto Formentini1, Geert Cornelis1, Jon Petter Gustafsson1
1Department of Soil and Environment, Swedish University of Agricultural Sciences, P. O. Box 7014, SE-750 07 Uppsala, Sweden.
Journal of hazardous materials
|October 14, 2023
概括
零价值铁 (ZVI) 颗粒有效地固定了污染的无氧地下水中的致癌. 这项研究表明,ZVI通过铁腐蚀产品增强了的保留,提供了一个有前途的现场补救策略.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 水处理 处理水的方法
背景情况:
- 地下水中的污染带来了重大致癌风险.
- 无毒含水层对补救提出了独特的挑战.
- 零价值铁 (ZVI) 在污染物封存方面的潜力得到了探索.
研究的目的:
- 为了研究商业零价值铁 (ZVI) 颗粒在从污染的无氧含水层沉积物中固定 (As) 的有效性.
- 在现场现实的条件下,阐明由ZVI控制As固定的地化学机制.
- 为了比较不同ZVI颗粒类型 (涂层与未涂层,纳米与微尺度) 的As去除性能.
主要方法:
- 从瑞典一个受污染的无氧含水层取沉积物和地下水样本.
- 四种商业零价值铁 (ZVI) 颗粒类型的应用.
- 使用X射线吸收光谱学 (XAS) 分析固相As和Fe的特异化.
- 通过染色学分离确定溶液相As物种化.
主要成果:
- 添加ZVI增加了溶液pH值,并有利于酸盐的形成,尽管降低了氧化还原潜力.
- 通过复杂结合新形成的Fe (III) (水氧化物),ZVI显著增强了A的保留.
- 与硫化ZVI相比,未涂层的ZVI颗粒显示出更高的性能.
- 颗粒大小 (纳米与微观) 对As固定效率的影响最小.
结论:
- 零价值铁 (ZVI) 颗粒是一种非常有效的策略,可以在受污染的无氧含水层中固定.
- 固定化主要是由Fe(III) (水氧化物和随后的结合的形成驱动的.
- 这些发现支持ZVI在地下水中进行现场长期治的应用.
- 在沉积物悬浮中观察到的固定机制不同于简单的As-spiked溶液中的固定机制.
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