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Coagulation/flocculation is a widely used water and wastewater treatment process due to its low cost, simplicity, and effectiveness. However, the process is not effective in the treatment of per- and polyfluoroalkyl substances (PFAS), the presence and treatment of which is an ongoing challenge for water providers. Here, we explore cationic surfactant-enhanced coagulation as a process modification to target the removal of PFAS in existing coagulation/flocculation systems. Batch experiments, in jar testing apparatus, were performed to assess the removal of two short-chain and two long-chain PFAS at an initial concentration of 10 µg/L with the addition of cetyltrimethylammoniumg chloride (CTAC) as the coagulant-aid. Our findings suggest that elevated coagulant dose (60 mg/L of alum or 100 mg/L of FeCl3) coupled with the addition of a cationic surfactant (1 mg/L of CTAC) significantly enhanced the removal of both short-chain (perfluorobutane sulfonate: PFBS removal to >40%) and long-chain PFAS (perfluorooctanoic acid: PFOA and perfluorooctane sulfonate: PFOS removal to >80%), with FeCl3 showing better performance than alum. Sulfonates (PFBS, PFOS) were shown to be removed more efficiently compared to carboxylates (PFBA, PFOA), presumably due to their higher hydrophobicity leading to better interactions with the flocs. Furthermore, CTAC in combination with traditionally used additives such as Powdered Activated Carbon (PAC), served as a better aid for PFAS treatment and improved the removal of PFBS, PFOA, and PFOS to >98%. This study highlights that introducing a cost-effective pre-treatment with a cationic surfactant to existing conventional treatment systems can improve the performance efficiency in treating PFAS-contaminated waters.
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This content will become publicly available on August 21, 2026
An Integrated Approach to Mapping Per- and Polyfluoroalkyl Substances Sorption in Sediments Using Electromagnetic Induction
Understanding the fate and transport of per- and polyfluoroalkyl substances (PFAS) at contaminated sites is crucial for effective remedial and regulatory decision-making. This interdisciplinary study offers a novel approach for estimating and mapping PFAS sorption properties and their impact on PFAS fate and transport. By integrating electromagnetic induction (EMI) surveys, physical and chemical sediment characterization, mineralogical characterization, and batch sorption experiments of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), we develop a comprehensive mapping of sorption dynamics. Sediments collected from a compound bar deposit were analyzed to establish correlations between EMI signal, sediment characteristics, and PFOA and PFOS sorption distribution coefficients (Kd). Sorption behavior and EMI response of these compounds were consistent with the sediments’ physical and chemical properties where Kd and electrical conductivity was higher with finer grain size, higher organic matter content, and higher aluminum and iron contents. The study demonstrates that EMI effectively maps PFAS sorption properties spatially, providing crucial insights into the sedimentological controls that govern both EMI responses and PFAS sorption. Correlation analysis yielded Pearson correlation values of 0.71 for EMI-PFOA Kd and 0.56 for EMI-PFOS Kd, underscoring the potential of EMI in predicting the spatial distribution of PFAS sorption in complex sedimentary environments. While these Pearson correlation values indicate moderate to strong correlations, their significance is amplified by the cost-effectiveness and extensive aerial coverage of EMI, the sparsity of sediment samples typically collected for batch sorption, and their spatial distribution. These results highlight the potential of EMI to identify sorption hotspots, thereby guiding targeted remediation efforts and enhancing site management strategies, ultimately reducing both costs and environmental impacts.
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- Award ID(s):
- 2048452
- PAR ID:
- 10640609
- Publisher / Repository:
- ACS Earth and Space Chemistry
- Date Published:
- Journal Name:
- ACS Earth and Space Chemistry
- Volume:
- 9
- Issue:
- 8
- ISSN:
- 2472-3452
- Page Range / eLocation ID:
- 2033 to 2044
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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