使用修改的静态头空间方法确定以太和铁乙醇多甲基和多甲基物质的温度依赖的空气-水分区
Viktória Licul-Kucera1, Annemarie P van Wezel1, Hans Peter H Arp2,3
1Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
Environmental science & technology
|July 28, 2025
概括
这项研究测量了新型基和多基物质 (PFAS) 的空气-水分区,并发现更长的碳链会增加分区. 对于这些PFAS,COSMOtherm提供了最准确的预测.
科学领域:
- 环境化学环境化学
- 物理化学 物理化学
背景情况:
- 和多基基物质 (PFAS) 是广泛使用的具有环境持久性的化学物质.
- 了解PFAS分区对于评估它们的环境命运和运输至关重要.
- 新型 PFAS 具有以太或硫连接是替代表面活性剂的转化产物.
研究的目的:
- 通过实验确定新型PFAS的温度依赖的空气-水分区行为.
- 将实验结果与来自各种模型的预测进行比较.
- 为了研究化学结构和温度对PFAS空气水分区的影响.
主要方法:
- 修改了静态头空间方法,具有可变的头空间/溶液比率,以测量无维空气/水分区系数 (Kaw).
- 由于目标PFAS的挥发性较低,对水阶段的分析.
- 实验温度范围在25°C至80°C之间.
主要成果:
- 逻辑K值在25°C时从-2.6到-1.0不等.
- 增加过碳链长度 (CF3-到C3F7-) 增加了Kaw大约1.5日志单位.
- 与实验数据相比,基于量子化学的COSMO热模型证明了最可靠的预测.
结论:
- PFAS空气水分区受 perfluorinated 碳链长度的影响,但以太/thioether 链接的影响不大.
- 分区的温度依赖性 (ΔU) 在不同结构中是一致的.
- COSMOtherm是预测新型PFAS的空气-水分区的一个有价值的工具.
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