| Perfluorinated compounds (PFCs) were produced and consumed as surfactants, repellents, additives, fire-fighting foams, polymer emulsifiers and insecticides for more than fifty years. PFCs are persistent, bioaccumulated and toxic chemicals, and ubiquitously distributed in water, sediment, human body and biota. PFCs have been detected in underground water, surface water, sea water, even the tap water all around the world. Especially, PFOS and PFOA are the most detected pollutants. Municipal wastewater treatment plants (WWTP) are now considered as the main source of PFCs discharged in the environment. Abundant consumption and release of the industrial wastewater cause the contamination of PFCs in the environment.The method of SPE-UPLC-MS/MS was used to determine 12 PFCs in wastewater from three wastewater treatment plants (WWTP) in Beijing, and it was proved to be fast and sensitive to quantitatively analyze the PFCs. Results show that the short chain PFCs including PFBA, PFPA, and PFBS were commonly present in influent and effluent in the wastewater treatment plants, and PFBS concentration was up to 253 ng/L. After the biological treatment, the concentrations of most PFCs in effluent decreased, but few PFCs had higher concentration possible due to the degradation of their precursors. In the advanced treatment process, reverse osmosis membrane had better removal efficiency for PFCs than ozone treatment.Coagulation was used to remove PFOS and PFOA from simulated surface water in water treatment plant. The effects of different coagulants, dose, solution pH, temperature, and turbidity were investigated. The results show that coagulation can reduce the PFOS and PFOA in the surface water through removal of suspended solids, but their concentrations in water are still high. The addition of powder active carbon before coagulation can significantly enhance the removal efficiency of PFOS and PFOA in the water.
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