通过介导的电化学先进氧化和紫外线去除氨的协同机制
Qiangang Li1, Guo-Hua Liu1, Hongbiao Du1
1Research Center for Low Carbon Technology of Water Environment, School of Environment and Nature Resources, Renmin University of China, Beijing, 100872, China.
Journal of environmental management
|January 10, 2024
概括
紫外线 (UV) 辐射增强了介导的电化学先进氧化 (Cl-EAO),用于废水中去除氨. 紫外线通过增加基 (Cl•) 度来促进氨氧化,使其成为主要的氧化剂.
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:
- 氨是废水中常见的污染物,对水生生态系统和人类健康构成风险.
- 电化学高级氧化工艺 (EAO) 与 (Cl-EAO) 结合,对清除氨有望.
- Cl-EAO与紫外线 (UV) 辐射之间的协同机制需要进一步阐明,以优化应用.
研究的目的:
- 为了比较Cl-EAO和UV-E/Cl系统的氨氧化性能.
- 在Cl-EAO过程中识别紫外线的协同机制.
- 为了评估UV-E/Cl在真正的家用废水中去除氨的有效性.
主要方法:
- 对氧化Cl-EAO和UV-E/Cl系统进行比较分析.
- 使用UV/氧化 (UV-ClO) 系统研究协同作用机制.
- 电子偏磁共振 (EPR) 分析,自由基抑制试验和稳定状态激素度的确定.
主要成果:
- 与Cl-EAO相比,添加紫外线增加了42.85%的氨去除率,同时降低了活性和酸盐产量.
- 紫外线显著增加了51.47%的基 (Cl•) 度,使其成为UV-E/Cl系统中主要的氧化剂.
- 紫外线还增加了基激素 (HO•) 和二基离子 (Cl2•−) 的度,改善了实际废水中的有机物质去除.
结论:
- 紫外线辐射显著提高了Cl-EAO的氨去除效率,通过增加关键的基因物种,特别是Cl•.
- 紫外线-E/Cl工艺在实际的家用废水中表现出强大的性能,即使有干扰性离子.
- 本研究阐明了UV-E/Cl技术的机制,突出了其在有效废水处理方面的潜力.
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