title: Adsorption behavior of sulfamethazine in an activated sludge process treating swine wastewater.
abstract: Swine wastewater is an important pollution source of antibiotics entering the aquatic environment. In this work, the adsorption behavior of sulfamethazine (SMN), a commonly-used sulfonamide antibiotic, on activated sludge from a sequencing batch reactor treating swine wastewater was investigated. The results show that the adsorption of SMN on activated sludge was an initially rapid process and reached equilibrium after 6hr. The removal efficiency of SMN from the water phase increased with an increasing concentration of mixed liquor suspended solids, while the adsorbed concentration of SMN decreased. Solution pH influenced both the speciation of SMN and the surface properties of activated sludge, thus significantly impacting the adsorption process. A linear partition model could give a good fit for the equilibrium concentrations of SMN at the test temperatures (i.e., 10, 20 and 30°C). The partition coefficient (Kd) was determined to be 100.5L/kg at 20°C, indicating a quite high adsorption capacity for SMN. Thermodynamic analysis revealed that SMN adsorption on activated sludge was an exothermic process. This study could help to clarify the fate and behavior of sulfonamide antibiotics in the activated sludge process and assess consequent environmental risks arising from sludge disposal as well.
authors.affiliation: Key Laboratory of Aquatic Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: wwben@rcees.ac.cn.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Ben
authors.affiliation: Key Laboratory of Aquatic Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: qiangz@rcees.ac.cn.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Qiang
authors.affiliation: Key Laboratory of Aquatic Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Yin
authors.affiliation: Key Laboratory of Aquatic Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Jiuhui
authors.initials: J
authors.lastname: Qu
authors.affiliation: Foreign Economic Cooperation Office, Ministry of Environmental Protection, Beijing 100035, China.
authors.forename: Xun
authors.initials: X
authors.lastname: Pan
mesh_terms: D000327:Adsorption; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D012722:Sewage / Q000737:chemistry*; D013418:Sulfamethazine / Q000737:chemistry*; D013552:Swine; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical
chemical_list: D000890:Anti-Infective Agents; D012722:Sewage; D014874:Water Pollutants, Chemical; D013418:Sulfamethazine
keywords: Activated sludge; Adsorption; Sulfonamide antibiotics; Swine wastewater treatment