超氧化离子对Cr (VI) 减少的作用由松树生物炭
1Yunnan Provincial Key Lab of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming 650500, Yunnan, China.
Journal of hazardous materials
|March 1, 2024
概括
生物炭主要通过液相反应显著降低水性六价 (Cr(VI)). 生物炭上的基产生超氧化基 (·O2-),这是这种Cr (VI) 减少过程的关键.
科学领域:
- 环境化学环境化学
- 材料科学 材料科学 材料科学
- 环境修复 环境修复
背景情况:
- 六价 (Cr(VI)) 是一种有毒的污染物,具有重大环境和健康风险.
- 生物炭表现出氧化还原活性,这表明了Cr (VI) 减少的潜力.
- 活性氧物种 (ROS) 在生物炭介导的Cr (VI) 减少中的特定作用仍然不清楚.
研究的目的:
- 在生物炭系统中量化评估Cr(VI) 吸附和减少.
- 为了区分不同ROS在生物炭-Cr (VI) 反应中的贡献.
- 确定生物炭功能组在ROS生成和Cr (VI) 减少中的作用.
主要方法:
- 在未经处理和无氧条件下的Cr(VI) 减少的比较.
- 使用尼托特拉蓝化物来灭超氧化基 (·O2-) 和单片氧 (1O2).
- 采用博姆定位来分析生物炭表面的功能组,并量化O2-.
主要成果:
- 在未经治疗的条件下,与无氧条件相比,Cr(VI) 的减少是无氧条件下的1.5倍.
- 超氧化基 (·O2-) 被确定为Cr (VI) 减少的主要贡献者,在火时减少了34%.
- 单点氧 (1O2) 起到了可以忽略不计的作用,这归因于2-2的更强的电子捐赠能力.
- 证实O2的减少过程主要发生在液态阶段.
- 在基和O2形成之间发现了显著的正相关性 (P < 0.05),表明基是主要电子捐赠者.
结论:
- 液相还原是通过生物炭去除Cr (VI) 的关键途径.
- 生物炭上的基功能组对于产生超氧化基 (·O2-) 是必不可少的,导致Cr (VI) 的减少.
- 这项研究提供了关键的理论见解,了解生物炭在Cr6修复中的有效性.
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