通过化纳米级零价值铁对Cr (VI) 的降低性分离
Mengjing Cao1, Yongxiang Zhang1
1Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing, 100124, China; Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China.
Journal of environmental management
|January 10, 2024
概括
破解化纳米级零价铁 (p-nZVI) 有效地从水中去除重金属. 这项研究优化了p-nZVI的制备,并评估了它在各种水类中的性能,显示了它的环保性和效率.
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:
- 纳米级零价铁 (nZVI) 是有效的减少重金属的去除.
- 环境风险和nZVI的局限性需要修改以提高稳定性和性能.
- 对nZVI的酸化可以改善其用于水处理的特性.
研究的目的:
- 为了准备和描述破裂的化纳米级零价铁 (p-nZVI).
- 调查p-nZVI对重金属离子,特别是CrVI的去除效率.
- 评估各种环境因素对移除过程的影响.
主要方法:
- 合成p-nZVI,其最佳P/Fe比率为0.5%.
- 在不同条件下 (剂量,温度,pH,共存离子) 进行批量实验,以研究Cr(VI的去除.
- 吸附和运动建模 (Langmuir,伪一级,伪二级),以了解去除机制.
主要成果:
- p-nZVI制备成功,最佳的P/Fe比为0.5%.
- 移除速率随着p-nZVI剂量和温度的增加而增加,符合兰格穆尔等温和和伪序动力学.
- 通过增加的pH值,溶解氧,SiO3^2-,SO4^2-,PO4^3-,NO3^-,HCO3^-,和湿酸 (HA) 抑制了Cr (VI) 的去除.
- 像Cd2+,Cu2+,Mg2+,Mn2+这样的离子促进了去除,而Ca2+则表现出抑制.
- 在模拟的地下水,海水,河水和城市废水废水中,p-nZVI表现良好.
结论:
- 破解p-nZVI是一种有效和环保的材料,用于从各种水源中去除重金属.
- 通过p-nZVI进行现场降解是Cr (VI) 去除的主要机制.
- 结构修饰和酸盐组吸附显著提高了p-nZVI对重金属的吸附和减少能力.
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