Abstract：
Perfluoroalkyl acids (PFAAs) are ubiquitous in nature and pose serious health risks to humans and animals. Limiting PFAA exposure requires novel technology for their effective removal from water. We investigated the efficacy of biosolid-based activated carbon (Bio-SBAC) in removing frequently detected PFAAs and their precursor fluorotelomer compounds at environmentally relevant concentrations (∼50 μg/L). Batch experiments were performed to investigate adsorption kinetics, isotherms, and leachability. Bio-SBAC achieved >95% removal of fluorotelomeric compounds, indicating that the need for PFAA removal from the environment could be minimised if the precursors were targeted. Kinetic data modelling suggested that chemisorption is the dominant PFAA adsorption mechanism. As evidenced by the isotherm modelling results, Freundlich adsorption intensity, n-1, values of <1 (0.707-0.938) indicate chemisorption. Bio-SBAC showed maximum capacities for the adsorption of perfluorooctanoic acid (1429 μg/g) and perfluorononanoic acid (1111 μg/g). Batch desorption tests with 100 mg/L humic acid and 10 g/L NaCl showed that Bio-SBAC effectively retained the adsorbed PFAA with little or no leaching, except perfluorobutanoic acid. Overall, this study revealed that Bio-SBAC is a value-added material with promising characteristics for PFAA adsorption and no leachability. Additionally, it can be incorporated into biofilters to remove PFAAs from stormwater, presenting a sustainable approach to minimise biosolid disposal and improve the quality of wastewater before discharge into receiving waters.
摘要：
全氟烷基酸（PFAA）在自然界中普遍存在，对人类和动物构成严重的健康风险。限制PFAA暴露需要新颖的技术以将其有效地从水中去除。我们调查了生物固体基活性炭（Bio-SBAC）在环境相关浓度（〜50μg/L）下去除经常检测到的PFAA及其前体氟调聚物化合物的功效。进行批量实验以研究吸附动力学，等温线，和可浸出性。Bio-SBAC实现了>95%的氟二聚体去除，这表明，如果将前体作为目标，则可以最大程度地减少从环境中去除PFAA的需求。动力学数据模型表明，化学吸附是主要的PFAA吸附机理。等温线建模结果证明，Freundlich吸附强度，n-1,值<1(0.707-0.938)表示化学吸附。Bio-SBAC显示出最大的全氟辛酸（1429μg/g）和全氟壬酸（1111μg/g）吸附能力。用100mg/L腐殖酸和10g/LNaCl进行的批量解吸试验表明，Bio-SBAC有效地保留了吸附的PFAA，很少或没有浸出，除了全氟丁酸.总的来说,这项研究表明，Bio-SBAC是一种增值材料，具有很有前途的PFAA吸附特性和无浸出性。此外,它可以被纳入生物过滤器，以去除雨水中的PFAA，提出了一种可持续的方法，以最大程度地减少生物固体的处置，并在排放到接收水域之前提高废水的质量。
