title: Metal precipitation in an ethanol-fed, fixed-bed sulphate-reducing bioreactor.
abstract: A batch upflow fixed-bed sulphate-reducing bioreactor has been set up and monitored for the treatment of synthetic solutions containing divalent iron (100mg/L and 200mg/L), zinc (100mg/L and 200mg/L), copper (100mg/L and 200mg/L), nickel (100mg/L and 200mg/L) and sulphate (1700 mg/L and 2130 mg/L) at initial pH 3-3.5, using ethanol as the sole electron donor. The reactor has been operated at the theoretical stoichiometric ethanol/sulphate ratio. Complete oxidation of ethanol has been achieved through complete oxidation of the intermediately, microbially produced acetate. This is mainly attributed to the presence of Desulfobacter postgatei species which dominated the sulphate-reducing community in the reactor. The reduction of sulphate was limited to about 85%. Quantitative precipitation of the soluble metal ions has been achieved. XRD and SEM-EDS analyses performed on samples of the produced sludge showed poorly crystalline phases of marcasite, covellite and wurtzite as well as several mixed metal sulphides.
authors.affiliation: National Technical University of Athens, School of Mining and Metallurgical Engineering, Laboratory of Environmental Science and Engineering, Heroon Polytechniou 9, 15780 Athens, Greece. pkousi@metal.ntua.gr
authors.forename: Pavlina
authors.initials: P
authors.lastname: Kousi
authors.forename: Emmanouela
authors.initials: E
authors.lastname: Remoundaki
authors.forename: Artin
authors.initials: A
authors.lastname: Hatzikioseyian
authors.forename: Fabienne
authors.initials: F
authors.lastname: Battaglia-Brunet
authors.forename: Catherine
authors.initials: C
authors.lastname: Joulian
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Kousteni
authors.forename: Marios
authors.initials: M
authors.lastname: Tsezos
mesh_terms: D000085:Acetates / Q000737:chemistry; D019149:Bioreactors; D003300:Copper / Q000737:chemistry; D000431:Ethanol / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D010100:Oxygen / Q000737:chemistry; D012722:Sewage; D013431:Sulfates / Q000737:chemistry*; D016999:Sulfur-Reducing Bacteria / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical; D018508:Water Purification / Q000379:methods; D014961:X-Ray Diffraction
chemical_list: D000085:Acetates; D008670:Metals; D012722:Sewage; D013431:Sulfates; D014874:Water Pollutants, Chemical; D000431:Ethanol; D003300:Copper; C017846:cupric sulfide; D010100:Oxygen