从自由中优化自由基产量,使用量身定制的紫外线发光二极管排放光谱
Anthony Pimentel1, Karl G Linden1
1Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 4001 Discovery Dr, Boulder, CO 80303, USA.
Water research
|December 8, 2023
概括
无紫外线LED与免费配对,通过优化光子使用,提供增强的废水处理. 这种先进的氧化过程 (AOP) 提高了水再利用应用的效率.
科学领域:
- 环境工程 环境工程
- 摄影化学的使用.
- 水处理技术水处理技术
背景情况:
- 废水再利用的传统紫外线高级氧化工艺 (AOP) 由于背景吸收和较低的激素促进剂吸收而面临限制.
- 低效率导致当前紫外线AOP反应器中光子的不足利用.
研究的目的:
- 评估使用较长波长的紫外线发光二极管 (LED) (265,280,300 nm) 与自由相匹配,以优化AOP中的光子利用.
- 调查背景吸收对再生水中激素生成和污染物转化动力学的影响.
主要方法:
- 使用紫外线LED和不同波长 (265,280,300 nm) 的自由进行基生成量子产量的实验验证.
- 导出pH和波长依赖的基于流动性的速率常数,使用酸和酸作为探针化合物.
- 用UV LED AOP处理回收水,以评估背景吸收效应和评估其他性能指标.
主要成果:
- 自由在280-300纳米范围内显示出显著的吸收,这对于常见的再利用水的基本pH至关重要.
- 经过实验确定的量子产量和速率常数为基和基的贡献提供了洞察力.
- 在回收水中的背景吸收被发现会影响激素生成和污染物降解动力学.
结论:
- 无紫外线LED与自由相结合的优化光谱输出可以提高废水再利用中的AOP效率.
- 了解波长特定的激素生成和吸收特性是最大化光子利用的关键.
- 这种方法为更高效和可持续的水处理提供了一个有希望的途径.
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