title: Co-adsorption of perfluorooctane sulfonate and phosphate on boehmite: Influence of temperature, phosphate initial concentration and pH.
abstract: The co-presence of perfluorooctane sulfonate (PFOS) and phosphate in wastewater of various industries has been detected. Removing PFOS and phosphate simultaneously before discharging sewage into natural water can decrease effectively the environmental risk caused by the combined pollution of PFOS and phosphate. In this study, laboratory batch experiments were conducted for investigating the co-adsorption of PFOS and phosphate on boehmite and the influences of temperature, phosphate initial concentration and pH on the co-adsorption. The adsorption thermodynamics and kinetics of PFOS and phosphate on boehmite were also investigated completely and systematically. The results showed that lower temperature favored the co-adsorptions of PFOS and phosphate. The adsorption of PFOS and phosphate on boehmite agreed well with the Langmuir isotherm and the adsorption parameters of thermodynamics are ΔH=-16.9 and -20.0kJmol-1(PFOS and phosphate), ΔS=-5.69 and -7.63Jmol-1K-1(PFOS and phosphate) and ΔG <0 (PFOS and phosphate). It demonstrated that the co-adsorption of PFOS and phosphate on boehmite is a spontaneously exothermic process. Moreover, the co-adsorption process can be described well by a pseudo-second-order kinetic model. With increasing phosphate initial concentration, more phosphate could be adsorbed on boehmite, while the adsorption of PFOS decreased at phosphate initial concentration of less than 30mgL-1and increased at that of larger than 30mgL-1. In the co-adsorption process, the adsorption amount of PFOS decreased with pH increasing, but that of phosphate changed little.
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Jin
authors.initials: J
authors.lastname: Qian
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Mengmeng
authors.initials: M
authors.lastname: Shen
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China. Electronic address: pfwang2005@hhu.edu.cn.
authors.forename: Peifang
authors.initials: P
authors.lastname: Wang
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Soil and Water Science, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Jing
authors.initials: J
authors.lastname: Hu
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Jun
authors.initials: J
authors.lastname: Hou
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Ao
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zheng
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Kun
authors.initials: K
authors.lastname: Li
authors.affiliation: Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, People's Republic of China; College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Liu
mesh_terms: D000327:Adsorption; D017738:Alkanesulfonic Acids / Q000032:analysis*; D000536:Aluminum Hydroxide / Q000737:chemistry*; D000537:Aluminum Oxide / Q000737:chemistry*; D005466:Fluorocarbons / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008962:Models, Theoretical; D010710:Phosphates / Q000032:analysis*; D013696:Temperature; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D017738:Alkanesulfonic Acids; D005466:Fluorocarbons; D010710:Phosphates; D014874:Water Pollutants, Chemical; D000536:Aluminum Hydroxide; C069471:aluminum oxide hydroxide; C076994:perfluorooctane sulfonic acid; D000537:Aluminum Oxide
keywords: Co-adsorption; Perfluorooctane sulfonate; Phosphate; Phosphate initial concentration; Temperature; pH