title: The influence of metal speciation in combustion waste on the efficiency of Cu, Pb, Zn, Cd, Ni and Cr bioleaching in a mixed culture of sulfur-oxidizing and biosurfactant-producing bacteria.
abstract: Metal leachability from ash and combustion slag is related to the physico-chemical properties, including their speciation in the waste. Metals speciation is an important factor that influences the efficiency of metal bioleaching from combustion wastes in a mixed culture of acidophilic and biosurfactant-producing bacteria. It was observed that individual metals tended to occur in different fractions, which reflects their susceptibility to bioleaching. Cr and Ni were readily removed from wastes when present with a high fraction bound to carbonates. Cd and Pb where not effectively bioleached when present in high amounts in a fraction bound to organic matter. The best bioleaching results were obtained for power plant slag, which had a high metal content in the exchangeable, bound to carbonates and bound to Fe and Mg oxides fractions- the metal recovery percentage for Zn, Cu and Ni from this waste exceeded 90%.
authors.affiliation: Warsaw University of Technology, Faculty of Environmental Engineering, Nowowiejska 20, 00-653 Warsaw, Poland. Electronic address: ewa.karwowska@is.pw.edu.pl.
authors.forename: Ewa
authors.initials: E
authors.lastname: Karwowska
authors.affiliation: Warsaw University of Technology, Faculty of Environmental Engineering, Nowowiejska 20, 00-653 Warsaw, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Wojtkowska
authors.affiliation: Warsaw University of Technology, Faculty of Environmental Engineering, Nowowiejska 20, 00-653 Warsaw, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Andrzejewska
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D008670:Metals / Q000145:classification / Q000378:metabolism*; D010084:Oxidation-Reduction; D013455:Sulfur / Q000378:metabolism*; D013501:Surface-Active Agents / Q000378:metabolism*
chemical_list: D008670:Metals; D013501:Surface-Active Agents; D013455:Sulfur
keywords: Bioleaching; Combustion wastes; Metals; Speciation