模拟pH对零价金属污染物封存的作用:通过零价减小酸盐
Jaeseon Park1, Joel Z Bandstra2, Paul G Tratnyek3
1Department of Earth System Sciences, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
Environmental science & technology
|January 26, 2024
概括
零价有效地将六价 (Cr(VI)) 隔离在一系列的pH值. 它的活性受pH的影响,从H+转变为H2O作为主要氧化剂.
科学领域:
- 环境化学环境化学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 六价 (Cr(VI)) 是一种有毒的环境污染物.
- 零价 (ZVMg) 显示了对Cr6修复的潜力.
- 了解pH对ZVMg活性的影响对于应用至关重要.
研究的目的:
- 调查pH在ZVMg.Cr(VI) 封存中的作用.
- 在动态pH条件下开发ZVMg腐蚀和Cr(VI) 去除的动态模型.
- 阐明控制ZVMg反应性的pH依赖机制.
主要方法:
- 没有缓冲的批量实验,初始pH值变化.
- 时间序列分析Cr (VI),Cr (III),Mg (II) 和pH.
- 全球适应的动力模型,结合了朗格穆尔-欣舍尔伍德动力学和过渡状态理论.
主要成果:
- 在初始pH值2.06.8的24小时内,ZVMg完全降低了CrVI,pH值上升到~10.
- 一个运动模型准确地预测了Cr (VI) 和Mg (II) 度的同步变化.
- 在pH 4以下,ZVMg的反应性表现出明显的pH依赖性行为,在pH 4以上表现出明显的pH依赖性行为.
结论:
- 通过ZVMg对Cr(VI) 的封存受到pH依赖反应通路的强烈影响.
- 主氧化剂 (H+与H2O) 的转变解释了观察到的pH依赖反应性.
- 开发的动力模型为优化基于ZVMg的修复策略提供了一个框架.
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