title: Effect of temperature on the sorption and desorption of perfluorooctane sulfonate on humic acid.
abstract: Sorption and desorption of perfluorooctane sulfonate (PFOS) on humic acid at different temperatures were studied. It was found that the sorption process could be modeled with power kinetic equation very well, suggesting that diffusion predominated the sorption of PFOS on the humic acid. The sorption capacity was doubled when the temperature increased from 5 to 35 degrees C, and thermodynamics parameters deltaG0 was calculated to be -7.11 to -5.04 kJ/mol, AHo was 14.2 kJ/mol, and deltaS0 was 69.5 J/(mol x K), indicating that the sorption was a spontaneous, endothermic, and entropy driven process. Desorption hysteresis occurred at all studied temperatures which suggested that humic acid may be an important sink of PFOS in the environment.
authors.affiliation: State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. jia.cx@163.com
authors.forename: Chengxia
authors.initials: C
authors.lastname: Jia
authors.forename: Chun
authors.initials: C
authors.lastname: You
authors.forename: Gang
authors.initials: G
authors.lastname: Pan
mesh_terms: D000327:Adsorption; D017738:Alkanesulfonic Acids / Q000737:chemistry*; D004785:Environmental Pollutants / Q000737:chemistry; D005466:Fluorocarbons / Q000737:chemistry*; D006812:Humic Substances / Q000032:analysis*; D013696:Temperature
chemical_list: D017738:Alkanesulfonic Acids; D004785:Environmental Pollutants; D005466:Fluorocarbons; D006812:Humic Substances; C076994:perfluorooctane sulfonic acid