Department of Environmental Engineering, National Chung Hsing University, 145 Xingda Rd., South Dist., Taichung City, 402, Taiwan.
Department of Environmental Engineering, National Chung Hsing University, 145 Xingda Rd., South Dist., Taichung City, 402, Taiwan.
J Hazard Mater. 2021 Jan 5;401:123387. doi: 10.1016/j.jhazmat.2020.123387. Epub 2020 Jul 4.
Passive sampling (PS) is a method employed to detect volatile organic compounds in groundwater and soil gas. This study attempted to manufacture a polydimethylsiloxane (PDMS) dialysis passive sampler for potential application in detecting trichloroethylene (TCE) in aqueous and gaseous phases. The equilibrium time of the passive sampler was initially determined, followed by multilayer passive sampling in a three-dimensional sandbox to construct a tomography of TCE vapor spatial distribution in the vadose zone above the saturated water level. The results indicated that an equilibrium time period of >10 d was required in the aqueous phase containing TCE concentrations ranging from 3 to 25 mg L, while an equilibrium time period of >12 d was necessary for TCE vapor concentrations ranging from 2.6-26 mg L. Therefore, a 14 d of equilibrium time was suggested for application of this passive sampler in detecting vapor and aqueous phase TCE. After collection of the passive samples from the three-dimensional sandbox, a three dimensional visualization was created, and it was demonstrated to be a reasonable way to simulate a three dimensional TCE distribution. It was confirmed that the passive sampler developed in this study is effective for assessing TCE contamination in the subsurface.
被动采样（PS）是一种用于检测地下水和土壤气体中挥发性有机化合物的方法。本研究试图制造一种用于检测水中和气相三氯乙烯（TCE）的聚二甲基硅氧烷（PDMS）透析被动采样器。首先确定了被动采样器的平衡时间，然后在三维沙箱中进行多层被动采样，以构建饱和水位以上包气带中 TCE 蒸汽空间分布的层析成像。结果表明，在含有 TCE 浓度为 3 至 25mg/L 的水溶液中，需要 >10d 的平衡时间，而在 TCE 蒸汽浓度为 2.6-26mg/L 的情况下，需要 >12d 的平衡时间。因此，建议将 14d 的平衡时间用于该被动采样器检测蒸气和水溶液中 TCE。从三维沙箱中收集被动样品后，创建了一个三维可视化，结果表明这是一种模拟三维 TCE 分布的合理方法。研究证实，本研究开发的被动采样器可有效评估地下水中的 TCE 污染。
