Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden.
PLoS One. 2020 Jun 25;15(6):e0234476. doi: 10.1371/journal.pone.0234476. eCollection 2020.
Soils contaminated with per- and polyfluoroalkyl substances (PFASs) are an important source for impacting drinking water delivery systems and surface water bodies world-wide, posing an urgent risk to human health and environmental quality. However, few treatment techniques have been tested for PFAS-contaminated soil hotspots. This study investigated the possibility of thermal desorption as a possible technique to remediate soils contaminated with multiple PFASs. Two fortified soils (∑9PFAS ≈ 4 mg kg-1) and one field-contaminated soil (∑9PFAS ≈ 0.025 mg kg-1) were subjected to a 75-min thermal treatment at temperatures ranging from 150 to 550°C. Soil concentrations of PFASs showed a significant decrease at 350°C, with the ∑9PFAS concentration decreasing by, on average, 43% and 79% in the fortified and field contaminated soils, respectively. At 450°C, >99% of PFASs were removed from the fortified soils, while at 550°C the fraction removed ranged between 71 and 99% for the field contaminated soil. In the field contaminated soil, PFAS classes with functional groups of sulfonates (PFSAs) and sulfonamides (FOSAs) showed higher removal than the perfluoroalkyl carboxylates (PFCAs). Thus thermal desorption has the potential to remove a wide variety of PFASs from soil, although more studies are needed to investigate the cost-effectiveness, creation of transformation products, and air-phase vacuum filtration techniques.
受多氟和全氟烷基物质（PFAS）污染的土壤是影响全球饮用水输送系统和地表水的一个重要来源，对人类健康和环境质量构成了紧迫的风险。然而，很少有处理技术被测试用于处理受 PFAS 污染的土壤热点。本研究调查了热解吸作为一种可能的修复技术来处理受多种 PFAS 污染的土壤的可能性。两种强化土壤（∑9PFAS≈4mgkg-1）和一种田间污染土壤（∑9PFAS≈0.025mgkg-1）在 150 至 550°C 的温度范围内进行了 75 分钟的热处理。土壤中 PFAS 的浓度在 350°C 时显著下降，强化土壤和田间污染土壤中∑9PFAS 的浓度分别平均下降了 43%和 79%。在 450°C 时，强化土壤中>99%的 PFAS 被去除，而在 550°C 时，田间污染土壤中去除的比例在 71%至 99%之间。在田间污染土壤中，带有磺酸盐（PFSAs）和磺酰胺（FOSAs）官能团的 PFAS 类别的去除率高于全氟烷基羧酸（PFCAs）。因此，热解吸有可能从土壤中去除各种 PFAS，尽管需要更多的研究来调查成本效益、转化产物的产生和空气相真空过滤技术。
