在Peracetic酸催化激活系统中识别和转化反应性物种,使用In Situ电子磁共振
Long Chen1, Ruohan Zhang1, Zhaoli Liu1
1College of Environmental Sciences and Engineering, The Key Laboratory of Water and Sediment Sciences, Peking University, Beijing 100871, P.R. China.
Environmental science & technology
|September 12, 2025
概括
基于乙酸 (PAA) 的先进氧化过程 (AOP) 产生了各种各样的反应物种,用于清除水污染. 这项研究使用电子磁共振 (EPR) 识别了基 (•OH) 和单点氧 (1O2) 等基因,从而促进了PAA-AOP的理解.
科学领域:
- 环境化学环境化学
- 水处理技术水处理技术
- 先进的氧化过程 先进的氧化过程
背景情况:
- 基于酸 (PAA) 的先进氧化过程 (AOP) 对水的净化至关重要.
- 准确识别PAA-AOP产生的各种反应物种仍然是一个挑战.
- 了解这些物种是优化水处理效率的关键.
研究的目的:
- 系统地研究和识别PAA催化激活系统中形成的反应物种.
- 为了比较同质 (金属离子诱导) 和异质 (物质诱导) 系统中的基质形成.
- 开发一种基于EPR的方法,用于在PAA-AOP中量化单片氧 (1O2).
主要方法:
- 构建金属离子诱导的同质和材料诱导的异质PAA催化激活系统.
- 在位电子磁共振 (EPR) 光谱用于检测基基 (•OH),基基 (•CH3),基基 (CH3C(O) OO和CH3C(O) O) 和单片氧 (1O2).
- 使用TEMP或其衍生品开发和应用基于EPR的1O2量化方法.
主要成果:
- 均质系统的基因配置受金属离子电子配置的影响.
- 异质系统的基因形成效率较低,但通过双重电子转移直接产生1O2.
- 光催化剂的性能取决于光生成的电子减少和孔氧化能力.
- 量化证实了1O2源于PAA自分解或CH3C的拉塞尔反应.
结论:
- 这项研究阐明了PAA-AOPs中反应性物种的形成和转化机制.
- 电子磁共振 (EPR) 是识别和量化这些系统中的物种的强大工具.
- 这些发现促进了对PAA-AOPs的基本理解,以改进水污染治理策略.
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