用VUV/UV/Cl−过程选择性氧化氨到:效率,途径和机制
Lingdan Wang1, Bing Chen1, Gaozu Liao1
1School of Environment, South China Normal University, Guangdong Provincial Engineering Technology Research Center for Drinking Water Safety, Guangdong Provincial Key Lab of Functional Materials for Environmental Protection, China.
Journal of hazardous materials
|April 15, 2025
概括
用离子对真空紫外线 (VUV) 辐射有效地去除高盐度水中的 (NH4+-N). 这种VUV/UV/Cl−过程将氨转化为高选择性的气 (N2).
科学领域:
- 环境化学环境化学
- 水处理技术水处理技术
- 氧化过程 氧化过程
背景情况:
- 循环水产养殖系统 (RMS) 的高盐度对清除氨 (NH4+-N) 提出了挑战.
- 将离子 (Cl−) 氧化为反应性物种 (RCS) 是 NH4+-N 除去的一个可行的策略.
- 真空紫外线 (VUV) 辐射为产生RCS提供了一种新的方法.
研究的目的:
- 研究VUV/UV/Cl−过程在模拟RMS水中去除NH4+-N的有效性.
- 阐明NH4+-N氧化机制并确定关键反应物种.
- 评估运营因素的影响,并评估实际应用中的性能.
主要方法:
- 模拟循环水耕系统 (RMS) 的水被使用VUV/UV/Cl−工艺处理.
- 分析了氨去除效率,选择性和中间产品.
- 研究了离子,二碳酸盐和其他因素在过程中的作用.
主要成果:
- 在VUV/UV/Cl−过程中实现了完全的NH4+-N氧化和88.3%的N2选择性.
- 氧化基 (ClO•) 被确定为通过化去除NH4+-N的主要RCS.
- 和二碳酸盐离子通过加速ClO•生成,显著促进了NH4+-N的去除.
- 该过程有效地从实际的海水和RMS水中去除了NH4+-N,NO2−-N和部分NO3−-N.
结论:
- 在高盐度下,VUV/UV/Cl−工艺对选择性氧化成气非常有效.
- 该机制涉及到ClO基的产生,导致的化.
- 这项技术在循环水产养殖系统中显示出大量的和总去除潜力.
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