Abstract
We present here an experimental investigation on the sorption of four perfluoroalkyl acids (PFAAs): namely, two perfluorocarbonic acids (PFCAs) – perfluorooctanoic acid (PFOA) and perfluorohexanoic acid (PFHxA); and two perfluorosulfonic acids – perfluorooctane sulfonate (PFOS) and, perfluorobutane sulfonic acid (PFBS) to polypropylene cover and carrier geotextiles commonly used in geosynthetic clay liners. The impacts of various operational parameters, such as sorbent mass, contact time, and initial PFAA concentration, were investigated. A bi-exponential adsorption model was observed to describe the adsorption kinetics for all PFAAs sufficiently. The model indicates two (probably physically) different types of adsorption sites involved in the PFAAs adsorption. The Freundlich and Langmuir equations well represented the adsorption isotherms. Furthermore, it was observed that PFAA sorption was strongly dependent on the end functional groups and perfluorinated carbon chain length of PFAAs. The maximum adsorption capacities for all PFAAs on geotextiles were consistent with results obtained for clay minerals, indicating that, in the absence of sufficient organic matter, sorption of PFAAs onto solids is mainly analyte and solution dependent. The results obtained and reported for the first time herein are imperative for understanding the fate and migration of PFAAs in modern geosynthetic composite liner systems.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.