有机硫化合物与臭氧在水相中的反应动力学
Simon A Rath1, Maria Lia Halder2, Urs von Gunten1
1Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Water research
|October 24, 2025
概括
这项研究量化了37种硫化合物与臭氧的水态反应速率,揭示了关键的反应性趋势. 这些发现改善了在臭氧化过程中对硫化合物命运的预测.
科学领域:
- 环境化学环境化学
- 水处理 处理水的方法
- 有机化学 有机化学
背景情况:
- 硫的功能组在药品,杀虫剂和天然有机化合物中普遍存在.
- 有限且矛盾的动力学数据存在于硫化合物与臭氧的水态反应中,阻碍了臭氧化过程中的命运预测.
- 准确的动力学数据对于理解和优化涉及臭氧化的水处理过程至关重要.
研究的目的:
- 确定37种含硫化合物与臭氧的水态反应的二次速率常数 (kO3).
- 确定不同硫功能群的臭氧反应的趋势和结构-活性关系.
- 提供可靠的数据集,以改善对臭氧化过程中硫化合物的行为评估.
主要方法:
- 利用竞争动力学来确定二次速率常数 (kO3).
- 作为一个pH独立的竞争对手 (kO3 = 1.0 × 106 M−1s−1) 的已确立的阿尔迪碳.
- 研究了pH值和结构特征对各种硫功能群的反应性的影响.
主要成果:
- 硫化物 (thioethers) 通常与臭氧 (kO3 ≈ 2 × 106 M−1s−1) 迅速反应,除了失活的结构.
- 醇表现出pH依赖的反应性 (kO3+SH ≈104 M−1s−1到kO3+S− ≈106 M−1s−1),观察到前所未有的pH依赖性.
- 反应性在不同的硫氧化状态和结构动机之间有很大的差异,硫酸盐具有高度反应性,而硫氧化物/硫酸硫酸盐无反应性.
结论:
- 该研究提供了关于硫化合物的臭氧反应性的全面数据集,揭示了基于功能组和结构特征的独特趋势.
- 观察到的醇,二硫化物 (如囊) 和非N-化异醇的pH依赖性为它们的臭氧化行为提供了新的见解.
- 生成的动力学数据增强了对臭氧化过程中硫化合物转化的理解,有助于评估环境命运和优化水处理.
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