通过添加水溶性盐来提高降解效率,循环性能和六价的去除速度
Junfeng He1, Yuheng Liang1, Hao Huang1
1Guangzhou Institute of Science and Technology, Guangzhou, 510540, China.
Environmental science and pollution research international
|October 18, 2023
概括
将盐添加到废水中显著提高了使用零价值铁 (ZVI) 的六价值的减少. 这种方法通过增强电磁合来提高反应速度和循环性能,以有效地去除重金属.
科学领域:
- 环境化学环境化学
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
背景情况:
- 六价 (Cr(VI)) 是一种有毒的重金属污染物.
- 零价值铁 (ZVI) 是有效的Cr(VI) 减少,但在反应速度和稳定性方面面临挑战.
- ZVI和溶液电荷之间的电磁合可以提高ZVI的性能.
研究的目的:
- 为了研究盐添加对ZVI的Cr (VI) 减少的影响.
- 为了提高ZVI的反应速度和循环性能,以去除Cr.
- 了解盐增强电磁合在ZVI介导的Cr降解中的机制.
主要方法:
- 使用微型ZVI,具有Fe0核心和FeOx外结构.
- 在六价溶液中添加各种盐 (CH3COONa,NaCl,NaNO3,Na2SO4).
- 分析反应动力学,循环性能,X射线衍射 (XRD) 和X射线光电子谱学 (XPS).
主要成果:
- 添加盐显著增加了Cr降解的反应速度和循环性能.
- 在CH3COONa的第一个循环中,Cr(VI) 在8分钟内降低到低于废水排放标准,并在20个循环后的20分钟内降低到低于废水排放标准.
- 与没有盐的实验相比,看似速率常数增加了近四倍,达到0.416分钟-1.1.
- XRD和XPS表明,随着盐的添加,形成了一个无形的氧化铁外.
- 鉴于盐阻碍Fe0-核心-电子转移通过Fe2O3.3,因此确定了优化的盐剂量.
结论:
- 将盐添加到废水中是一种有效的策略,可以通过使用ZVI来提高六价的减少.
- 盐增加了溶液电荷和ZVI之间的电磁合,激活了减氧反应,改善了重金属的去除.
- 该研究提供了一种新的方法,用于提高ZVI在废水处理中的效率和可重复使用性.
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