Sorption of perfluoroalkyl substances in sewage sludge

• Published in: Environmental science and pollution research international Vol. 23; no. 9; pp. 8339 - 8348
• Main Authors: Milinovic, Jelena, Lacorte, Silvia, Rigol, Anna, Vidal, Miquel
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2016; Springer Nature B.V; Springer Verlag
• Subjects: Absorció; Absorption; Absorption, Physicochemical; Acids; Alkanesulfonic Acids - chemistry; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Caprylates - chemistry; Carbon; Contaminants persistents; Desorption; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; Fluorocarbons - analysis; Fluorocarbons - chemistry; Hydrophobicity; Isotherms; Llots de depuradora; Perfluoroalkyl & polyfluoroalkyl substances; Perfluorocarbons; Perfluorochemicals; Perfluorooctane sulfonic acid; Perfluorooctanoic acid; Persistent pollutants; Pollutants; Polyethylene; Research Article; Risk taking; Sedimentation & deposition; Sewage - chemistry; Sewage sludge; Sewage treatment plants; Sludge; Sorption; Studies; Sulfonic Acids - chemistry; Surfactants; Waste Water Technology; Water Management; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - chemistry; Water Pollution Control; Water treatment; Switzerland; Germany; Spain; Sorption; Perfluorobutanesulfonic acid; Desorption; Perfluorooctanoic acid; Perfluorooctanesulfonic acid; Sewage sludge
• ISSN: 0944-1344; 1614-7499; 1614-7499
• DOI: 10.1007/s11356-015-6019-9

The sorption behaviour of three perfluoroalkyl substances (PFASs) (perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutanesulfonic acid (PFBS)) was studied in sewage sludge samples. Sorption isotherms were obtained by varying initial concentrations of PFOS, PFOA and PFBS. The maximum values of the sorption solid–liquid distribution coefficients (K d,max ) varied by almost two orders of magnitude among the target PFASs: 140–281 mL g −1 for PFOS, 30–54 mL g −1 for PFOA and 9–18 mL g −1 for PFBS. Freundlich and linear fittings were appropriate for describing the sorption behaviour of PFASs in the sludge samples, and the derived K F and K d,linear parameters correlated well. The hydrophobicity of the PFASs was the key parameter that influenced their sorption in sewage sludge. Sorption parameters and log(K OW ) were correlated, and for PFOS (the most hydrophobic compound), pH and Ca + Mg status of the sludge controlled the variation in the sorption parameter values. Sorption reversibility was also tested from desorption isotherms, which were also linear. Desorption parameters were systematically higher than the corresponding sorption parameters (up to sixfold higher), thus indicating a significant degree of irreversible sorption, which decreased in the sequence PFOS > PFOA > PFBS.