Effects of salinity on the adsorption behavior of perfluorinated and polyfluoroalkyl substances(PFAS)at the seawater-sediment interface
In order to understand adsorption kinetics and thermodynamics of per-and polyfluoroalkyl substances(PEAS),the five PFAS components were detected in the simulated seawater-sediment environments in this study.The adsorption capacity of perfluorooctane sulfonic acid(PFOS)under varying salinity conditions was found to be greater than that of perfluorooctanoic acid(PFOA)with the same carbon-fluorine chain length.The equilibrium adsorption capacity of PFOS in sediments was observed to be higher than that of its alternative,potassium 9-chlorohexadecafluoro-3-oxanonane-1-sulfonate(9C1-PF3ONS);and the equilibrium adsorption capacity of PFOA in sediments was greater than that of its alternative,hexafluoropropylene oxide dimeric acid(HFPO-DA),but lower than another alternative,hexafluoropropylene oxide trimeric acid(HFPO-TA).A strong positive correlation was observed between the Kd values of PFAS and salinity levels.The sorption of PFAS onto sediments exhibited an upward trend as the salt concentration increased.The adsorption mechanism of PFAS involved both hydrophobic interactions and electrostatic interactions.
perfluorinated and polyfluoroalkyl substances(PFAS)seawatersedimentsalinityadsorptionemerging contaminants
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维普
