在零价值铁系统中通过氧化剂激活促进了铁的腐蚀和随后的六价去除
Weiting Chen1, Bing Li1, Weizhao Yin2
1School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.
Chemosphere
|February 7, 2024
概括
添加KMnO4,NaClO和Na2S2O8等氧化剂显著提高了零价值铁 (ZVI) 在去除有毒六价值 (CrVI) 的性能. 这些氧化剂增强了铁的腐蚀,形成了新的矿物质,提高了Cr6的去除效率和过器的寿命.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 水处理 处理水的方法
背景情况:
- 零价值铁 (ZVI) 对于重金属的去除是有效的,但受到Cr (VI) 沉物的被动化,从而降低了效率.
- 铁沉的低导电性阻碍了铁的腐蚀,并限制了ZVI系统中的Cr (VI) 去除速度.
研究的目的:
- 研究氧化剂 (KMnO4,NaClO,Na2S2O8) 的使用,以增强由ZVI.
- 了解ZVI/氧化剂系统中改进的Cr (VI) 去除背后的机制.
主要方法:
- 批量测试和柱体实验使用ZVI进行,使用和不使用三种不同的氧化剂.
- 固态相特性被用来分析矿物质形成和表面特性.
- 循环和长期柱体实验评估了ZVI/氧化剂系统的稳定性和容量.
主要成果:
- 与ZVI单独 (9.8%) 相比,ZVI/氧化剂系统 (ZVI/KMnO4,ZVI/NaClO,ZVI/Na2S2O8) 显示出明显更高的Cr (VI) 去除率 (31.5%-65.9%).
- 氧化剂的添加促进了铁的腐蚀,并导致了二级矿物质的形成,如勒皮多克洛,铁和磁铁,这些矿物提供了更多的反应地点.
- 采用ZVI/NaClO柱的Cr (VI) 清除能力是ZVI柱的34.8倍,寿命也比ZVI柱长.
结论:
- 氧化剂通过促进铁的腐蚀和二次矿物形成,有效地增强ZVI的Cr(VI) 去除.
- ZVI/氧化剂系统提供了一个稳定且有前途的方法,用于在实际的过箱中进行Cr (VI) 整治.
- 这项研究为使用基于ZVI的技术提高Cr (VI) 清除效率提供了新的见解.
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