二甲A转化由生物炭支持后硫化纳米级零价值铁:从控制和溶剂动态同位素效应的机械见解
Feilong Gao1, Mingyi Zhang1, Shakeel Ahmad1
1MOE Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
Journal of hazardous materials
|July 17, 2023
概括
在生物炭 (S-nZVI/BC) 上合成的硫化纳米级零价值铁有效降解四博二甲 (TBBPA). 这种先进的材料显示出对环境修复的增强反应性和选择性.
科学领域:
- 环境化学环境化学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 甲 (TBBPA) 是一种在受污染的地下水中发现的持久性有机污染物.
- 纳米级零价值铁 (nZVI) 是地下水整治的一个有希望的材料,但它的效率可能是有限的.
- 对nZVI的表面修饰对于提高其反应性和选择性至关重要.
研究的目的:
- 为了合成和描述在生物炭 (S-nZVI/BC) 上沉积的硫化后纳米级零价值铁,用于TBBPA降解.
- 调查硫化度和生物炭修饰对nZVI的特性和性能的影响.
- 阐明降解机制,并确定控制S-nZVI/BC.反应性和选择性的关键因素.
主要方法:
- 通过控制FeSx外厚度的硫化后方法合成S-nZVI/BC.
- 使用分析外厚度,形态,S含量/规格/分布,疏水性和电子转移能力的技术进行全面的表征.
- 与nZVI/BC.相比,四博二甲 (TBBPA) 降解实验评估反应性和选择性.
- 溶剂动态同位素效应 (SKIEs) 分析,以探测降解机制.
主要成果:
- 与nZVI/BC.相比,S-nZVI/BC对TBBPA降解的反应性 (8.913.2倍) 和选择性 (58.4228.9倍) 显著更高.
- 生物炭修饰增强了电子转移和疏水性,同时抑制了S-nZVI表面氧化.
- 最佳的FeSx外厚度 (~32 nm) 最大化了Fe0核心和FeSx外之间的关联,导致了更高的反应性.
- 较高的表面和颗粒硫与铁的比率 ([S/Fe]) 促进了选择性,颗粒比率更有影响.
- 直接电子转移被确定为主要的除途径,有助于更高的选择性.
结论:
- S-nZVI/BC 是一种高效且有前景的材料,用于修复被TBBPA污染的地下水.
- 控制FeSx外厚度和利用生物炭支持是优化nZVI性能的关键策略.
- 降解机制主要由电子转移驱动,由S-nZVI/BC.的特定表面特性增强.
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