title: Comparison of the sorption behaviors and mechanisms of perfluorosulfonates and perfluorocarboxylic acids on three kinds of clay minerals.
abstract: The sorption of four perfluoroalkyl acids (PFAAs) [perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid (PFOA) and perfluorohexanoic acid (PFHxA)] on three typical minerals [montmorillonite (MM), kaolinite (KL) and hematite (HM)] was studied. The sorption of PFOS and PFHxS was much stronger than PFOA and PFHxA. The sorption of each PFAA on the minerals followed an order of HM>KL>MM, even though MM was positively while KL and HM were negatively charged, implying that the sorption is driven by some other interactions besides electrostatic attraction. The sorption decreased with an increase in pH and a decrease in ionic strength of the solution, and their impacts on PFOS were much stronger than other three PFAAs. Surface complexing and hydrogen-bonding could make great contributions to the sorption of PFOS on the minerals. The results are important for understanding the transport and fate of PFAAs in sediment and ground water.
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China.
authors.forename: Lixia
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China.
authors.forename: Jingna
authors.initials: J
authors.lastname: Bian
authors.affiliation: Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China.
authors.forename: Yahui
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China. Electronic address: zhuly@nankai.edu.cn.
authors.forename: Lingyan
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China.
authors.forename: Zhengtao
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000327:Adsorption; D017738:Alkanesulfonic Acids / Q000302:isolation & purification*; D000538:Aluminum Silicates / Q000737:chemistry*; D001546:Bentonite / Q000737:chemistry; D002208:Caproates / Q000302:isolation & purification*; D002210:Caprylates / Q000302:isolation & purification*; D000077215:Clay; D005290:Ferric Compounds / Q000737:chemistry; D005466:Fluorocarbons / Q000302:isolation & purification*; D006860:Hydrogen Bonding; D007616:Kaolin / Q000737:chemistry; D009994:Osmolar Concentration; D055672:Static Electricity
chemical_list: D017738:Alkanesulfonic Acids; D000538:Aluminum Silicates; D002208:Caproates; D002210:Caprylates; D005290:Ferric Compounds; D005466:Fluorocarbons; D001546:Bentonite; C000499:ferric oxide; D007616:Kaolin; C023036:perfluorooctanoic acid; C076994:perfluorooctane sulfonic acid; D000077215:Clay; C479228:perfluorohexanoic acid
keywords: Clay minerals; Complexation; Electrostatic interaction; Hydrogen bonding; Perfluoroalkyl acids (PFAAs); Sorption mechanisms