九种与饮用水相关的 perfluoroalkyl 化学物质的强基离子交换选择性
David G Wahman1, Samantha J Smith1, Eric J Kleiner1
1Center for Environmental Solutions & Emergency Response, U.S. Environmental Protection Agency, Cincinnati, Ohio 45268, United States.
概括
这项研究量化了使用离子交换树脂对化物的和多醇基物质 (PFAS) 选择性. 结果显示,PFAS具有较高的选择性,可以更好地建模饮用水处理.
科学领域:
- 环境化学环境化学
- 水处理技术水处理技术
- 分析化学 分析化学
背景情况:
- 和多基基物质 (PFAS) 是饮用水中的持久污染物.
- 传统的水处理方法难以有效地去除PFAS.
- 了解PFAS与离子交换树脂的相互作用对于开发先进的处理策略至关重要.
研究的目的:
- 为了确定离子交换树脂对各种PFAS化合物的选择性,相对于化物.
- 调查PFAS化学结构 (链长,功能组) 对选择性的影响.
- 评估已建立的离子交换模型对于PFAS去除的适用性.
主要方法:
- 对使用三种强基离子交换凝树脂的9种饮用水相关的PFAS进行了调查选择性系数 (
- 在饮用水中的相关度 (≤500 ng/L) 进行了实验.
- 进行多解决方案竞争实验以验证模型预测.
主要成果:
- 化物对PFAS的选择性 (
- 选择性随着 PFAS 碳链长度的增加而增加,对于具有相同链长的 perfluoroalkyl carboxylic 酸 (PFCAs) 而不是 perfluoroalkyl sulfonic 酸 (PFSAs) 的选择性更高.
- PFAS的行为一般遵循质量作用定律,但最长链的化合物除外.
- 多元组件实验证实,二进制同热带衍生的选择性值可以预测多溶解系统的行为.
结论:
- 强大的基离子交换树脂显示出从饮用水中去除PFAS的巨大潜力.
- 量化选择性系数为完善用于PFAS修复的离子交换模型提供了必要的数据.
- 这项研究促进了开源模型的开发和验证,以优化PFAS处理过程.
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