title: Characterisation of the mineral fraction in extracellular polymeric substances (EPS) from activated sludges extracted by eight different methods.
abstract: This work characterises the mineral fraction of EPS extracts obtained using eight different methods from two activated sludges by total mineral content determination, Fourier Transformed Infrared spectrometry and with scanning electron microscopy coupled with an EDX probe. Despite EPS dialysis, the EPS extracts displayed a mineral fraction between 2% and 40% of the EPS dry weight depending on the extraction method used. The main mineral elements found in the EPS extract were Ca, Mg, Na, K, Al, Fe, Mn, P, Si and S, but their contents were strongly affected by the extraction method used. Some of the minerals are associated with the organic molecules within the EPS. The presence of mineral particles of various compositions and structures (clays, quartz or carbonate) in the EPS extract with a wide range in size was clearly demonstrated. Moreover, the association of metallic elements with the mineral particles in the EPS extract was highlighted.
authors.affiliation: Université de Limoges, Groupement de Recherche Eau Sol Environnement (EA 4330), Faculté des Sciences et Techniques, 123 Av. Albert Thomas, 87 060 Limoges, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Bourven
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Joussein
authors.forename: Gilles
authors.initials: G
authors.lastname: Guibaud
mesh_terms: D002498:Centrifugation; D005591:Chemical Fractionation / Q000379:methods*; D003890:Desiccation; D005110:Extracellular Space / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008903:Minerals / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014865:Waste Disposal, Fluid; D018508:Water Purification
chemical_list: D008903:Minerals; D011108:Polymers; D012722:Sewage