有效的Fe (III) /Fe (II) 循环,由L-氨酸功能化零价值铁介导,以增强Cr (VI) 去除
Fengfeng Zhou1, Qiangling Liu1, Yaxin Qin2
1Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 430205, People's Republic of China.
Journal of hazardous materials
|May 28, 2023
概括
修改L-氨酸的零价值铁 (C-ZVIbm) 显著提高了 (VI) 的去除效率. 这种表面修饰促进了电子转移,促进了有毒Cr6的减少,使其变得不那么有害.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 化学 化学 化学
背景情况:
- 六价 (Cr(VI)) 是一种有毒的污染物,需要有效的去除方法.
- 零价值铁 (ZVI) 对于Cr (VI) 补救是有效的,但可以通过表面被动化来限制.
- 修改ZVI的表面可以提高它的反应性和污染物去除能力.
研究的目的:
- 通过表面修改,提高零价值铁 (ZVI) 的Cr (VI) 去除效率.
- 通过修改ZVI.来研究增强Cr(VI) 移除的机制.
- 探索L-氨酸作为ZVI表面修饰剂的潜力.
主要方法:
- L-氨酸 (Cys) 在零价值铁 (ZVI) 上进行球磨,以产生C-ZVIbm.
- 使用ATR-FTIR,电化学分析和ESR光谱学进行表征.
- (VI) 清除效率测试和吸附异温/动力学研究.
主要成果:
- 在30分钟内,C-ZVI实现了99.6%的CrVI去除,明显高于未经修改的ZVI (7.3%).
- 在ZVI表面,L-氨酸形成了-COO-Fe复合体,通过双核双核内部球体复合体增强了Cr(VI) 的吸附.
- 吸附遵循弗洛伊德利希等温和和伪二阶动力学.
- Cys降低了Fe (III) /Fe (II) 的氧化还原潜力,促进了Fe (0) 的电子转移和Cr (VI) 减少到Cr (III).
结论:
- 用L-氨酸修改ZVI的表面是一种高度有效的策略,可以增强Cr (VI) 的去除.
- 该机制涉及改善吸附和促进Fe (III) /Fe (II) 循环,促进Cr (VI) 减少.
- 这种方法为开发高效的Cr (VI) 整治技术提供了一个有希望的途径.
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