与金属离子的复合影响溶解有机物质的化反应性:新出现的消毒副产品的结构反应学
Qian Hu1,2, Mingxuan Lou1,2, Ruigang Wang1,2
1College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China.
Environmental science & technology
|July 23, 2024
概括
铁和离子与溶解有机物 (DOM) 形成复合物,增加饮用水中有害的化消毒副产品 (Cl-DBPs) 的形成. 这突显了潜在的健康风险和需要更严格的金属控制标准.
科学领域:
- 环境化学环境化学
- 水处理科学水处理科学
- 有机地化学 有机地化学
背景情况:
- 金属离子很容易与溶解有机物 (DOM) 形成复合体,改变DOM的化学特性和反应性.
- 了解金属-DOM相互作用对于预测水化过程中消毒副产品 (DBPs) 的形成至关重要.
研究的目的:
- 研究铁 (Fe3+) 和 (Zn2+) 离子对化系统中未知化消毒副产品 (Cl-DBPs) 的形成的影响.
- 阐明金属-DOM复合影响DOM化学和反应性的机制.
主要方法:
- 涉及Fe3+和Zn2+与DOM的复杂化实验.
- 在受控系统中化金属-DOM复合物.
- 使用先进的分析技术分析DOM转换和Cl-DBP形成.
- 构建大小-反应性连续网络以了解分子转换.
主要成果:
- Fe3+优先复合与基和基组,而Zn2+在DOM中偏好氨基组.
- 金属-DOM复合产生了富含电子的中心,促进了电友性攻击,促进了分子转化 (脱碳化,去胺化).
- 与Fe3+和Zn2+的复合使未知的多化Cl-DBPs的丰度分别增加了9.6%和14.2%,通过由C-O-金属桥促进的基化.
结论:
- 金属离子显著改变DOM化学和反应性,导致潜在有害Cl-DBPs的形成增加.
- 金属-DOM复合增强了特定Cl-DBPs的产生,在饮用水中构成潜在的健康风险.
- 为了减轻这些风险,对水处理中的金属离子进行更严格的科学控制标准是必要的.
相关概念视频
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