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Henk Dijkman - One of the best experts on this subject based on the ideXlab platform.
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Application of sulfate reduction for the biological conversion of Anglesite (PbSO4) to galena (PbS)
Hydrometallurgy, 2008Co-Authors: Anke Schröder-wolthoorn, Simon Kuitert, Henk Dijkman, Jacco L. HuismanAbstract:Abstract In a bench scale trial biological sulfate reduction was applied to convert Anglesite (PbSO4) to galena (PbS). Anglesite is a main constituent in waste fractions such as lead paste from spent car batteries or residues from (in)direct leaching processes. The goal of this study was to develop a technology to decrease lead (Pb) emissions by converting PbSO4 from a waste fraction to PbS, which can be recovered using electrochemical processes. The conversion of PbSO4 to PbS is based on the biological reduction of sulfate and the consequent precipitation of PbS. First sulfate is biologically reduced to sulfide. Secondly, the Pb2+ from the PbSO4 reacts chemically with the sulfide resulting from the first reaction. A bench-scale reactor was started up using sulfate-containing influent. The reactor was seeded with biocatalyst from several full-scale reactors. PbSO4-containing residue was added batch-wise when the formation of sulfide started. The residue contained mainly PbSO4 (51.7%), sulfate (SO42−, 19.9%) and elemental sulfur (S0, 15.1%). PbS precipitates in the bioreactor due to the near-neutral pH at which the sulfate reduction process is carried out. From the electron balance and chemical analyses it was concluded that both sulfate and sulfur present in the residue were biologically reduced. The formation of PbS was confirmed by the increased Pb:O ratio in the sludge (1:0.1) relative to the Pb:O ratio in the PbSO4-containing residue (1:3.3). A potential large-scale application is proposed.
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Application of Sulfate Reduction for the Biological Conversion of Anglesite to Galena
Advanced Materials Research, 2007Co-Authors: Anke Wolthoorn, Simon Kuitert, Henk Dijkman, Jacco L. HuismanAbstract:In a bench scale trial biological sulfate reduction was applied to convert Anglesite (PbSO4) to galena (PbS). Anglesite is a main constituent of waste fractions such as the residue from an indirect leaching process or in lead paste from spent car batteries. The goal of this study was to develop a technology to decrease the lead (Pb) emissions by converting PbSO4 from a waste fraction into PbS, which can be recovered from the waste fraction using a flotation process or an electrochemical process. The conversion of Anglesite to galena is based on the biological sulfate reduction process and a metal precipitation process. First sulfate is biologically reduced to sulfide. Secondly, the Pb2+ from the PbSO4 reacts chemically with the sulfide resulting from the first reaction. A bench-scale reactor was started up using sulfate- and sulfur-containing influent. The reactor was seeded with biocatalyst from several full-scale reactors. Anglesite-containing residue was added batch-wise when the formation of sulfide started. The residue contained mainly PbSO4 (51.7%), sulfate (SO4 2-, 19.9%) and elemental sulfur (S0, 15.1%). Galena precipitates in the bioreactor due to the near-neutral pH at which sulfate reduction is carried out. During the experiment a surplus of sulfide relative to Pb was maintained to prevent the formation of PbCO3 and the accompanying pH decrease that would unavoidable result in the inhibition of the biocatalyst. Both sulfate and sulfur present in the residue were biologically reduced. The formation of PbS was confirmed by the increased Pb:O ratio of the sludge (1:0.03) relative to the Pb:O ratio of the residue (1:0.3). A potential large-scale application is proposed.
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Biological Conversion of Anglesite (PbSO4) and Lead Waste from Spent Car Batteries to Galena (PbS)
Biotechnology progress, 2002Co-Authors: Jan Weijma, Klaas De Hoop, Wobby Bosma, Henk DijkmanAbstract:Lead paste, a solid mixture containing PbSO(4), PbO(2), PbO/Pb(OH)(2) precipitate, and elemental Pb, is one of the main waste fractions from spent car batteries. Biological sulfidation represents a new process for recovery of lead from this waste. In this process the lead salts in lead paste are converted to galena (PbS) by sulfate-reducing bacteria. This paper investigates a continuous process for sulfidation of Anglesite (PbSO(4)), the main constituent of lead paste, and lead paste, consisting of a laboratory-scale gas-lift bioreactor to which a slurry of Anglesite or lead paste was supplied. Sulfate or elemental sulfur was added as an additional sulfur source. Hydrogen gas served as an electron donor for the biological reduction of sulfate and elemental sulfur to sulfide by sulfate- and sulfur-reducing bacteria. Anglesite was almost completely converted to galena at a loading rate of 19 kg of PbSO(4) m(-)(3) day(-)(1), producing a sludge of which the crystalline lead phases consisted of >98% PbS (galena) and 1-2% elemental Pb. With lead paste, stable sulfidation rates of up to 17 kg of lead paste m(-)(3) day(-)(1) were demonstrated, producing a sludge of which the crystalline lead phases consisted of an estimated >96% PbS, 1-2% elemental Pb, and 1-2% PbO(2).
Jacco L. Huisman - One of the best experts on this subject based on the ideXlab platform.
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Application of sulfate reduction for the biological conversion of Anglesite (PbSO4) to galena (PbS)
Hydrometallurgy, 2008Co-Authors: Anke Schröder-wolthoorn, Simon Kuitert, Henk Dijkman, Jacco L. HuismanAbstract:Abstract In a bench scale trial biological sulfate reduction was applied to convert Anglesite (PbSO4) to galena (PbS). Anglesite is a main constituent in waste fractions such as lead paste from spent car batteries or residues from (in)direct leaching processes. The goal of this study was to develop a technology to decrease lead (Pb) emissions by converting PbSO4 from a waste fraction to PbS, which can be recovered using electrochemical processes. The conversion of PbSO4 to PbS is based on the biological reduction of sulfate and the consequent precipitation of PbS. First sulfate is biologically reduced to sulfide. Secondly, the Pb2+ from the PbSO4 reacts chemically with the sulfide resulting from the first reaction. A bench-scale reactor was started up using sulfate-containing influent. The reactor was seeded with biocatalyst from several full-scale reactors. PbSO4-containing residue was added batch-wise when the formation of sulfide started. The residue contained mainly PbSO4 (51.7%), sulfate (SO42−, 19.9%) and elemental sulfur (S0, 15.1%). PbS precipitates in the bioreactor due to the near-neutral pH at which the sulfate reduction process is carried out. From the electron balance and chemical analyses it was concluded that both sulfate and sulfur present in the residue were biologically reduced. The formation of PbS was confirmed by the increased Pb:O ratio in the sludge (1:0.1) relative to the Pb:O ratio in the PbSO4-containing residue (1:3.3). A potential large-scale application is proposed.
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Application of Sulfate Reduction for the Biological Conversion of Anglesite to Galena
Advanced Materials Research, 2007Co-Authors: Anke Wolthoorn, Simon Kuitert, Henk Dijkman, Jacco L. HuismanAbstract:In a bench scale trial biological sulfate reduction was applied to convert Anglesite (PbSO4) to galena (PbS). Anglesite is a main constituent of waste fractions such as the residue from an indirect leaching process or in lead paste from spent car batteries. The goal of this study was to develop a technology to decrease the lead (Pb) emissions by converting PbSO4 from a waste fraction into PbS, which can be recovered from the waste fraction using a flotation process or an electrochemical process. The conversion of Anglesite to galena is based on the biological sulfate reduction process and a metal precipitation process. First sulfate is biologically reduced to sulfide. Secondly, the Pb2+ from the PbSO4 reacts chemically with the sulfide resulting from the first reaction. A bench-scale reactor was started up using sulfate- and sulfur-containing influent. The reactor was seeded with biocatalyst from several full-scale reactors. Anglesite-containing residue was added batch-wise when the formation of sulfide started. The residue contained mainly PbSO4 (51.7%), sulfate (SO4 2-, 19.9%) and elemental sulfur (S0, 15.1%). Galena precipitates in the bioreactor due to the near-neutral pH at which sulfate reduction is carried out. During the experiment a surplus of sulfide relative to Pb was maintained to prevent the formation of PbCO3 and the accompanying pH decrease that would unavoidable result in the inhibition of the biocatalyst. Both sulfate and sulfur present in the residue were biologically reduced. The formation of PbS was confirmed by the increased Pb:O ratio of the sludge (1:0.03) relative to the Pb:O ratio of the residue (1:0.3). A potential large-scale application is proposed.
Olli H. Tuovinen - One of the best experts on this subject based on the ideXlab platform.
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Solid-phase controls on lead partitioning in laboratory bioleaching solutions
Hydrometallurgy, 2013Co-Authors: Jerry M. Bigham, Ömer Faruk Algur, F. Sandy Jones, Olli H. TuovinenAbstract:Abstract The purpose of the work was to examine the co-precipitation of Fe(III) and Pb(II) in Acidithiobacillus ferrooxidans cultures under ambient temperature conditions. The competitive formation of plumbojarosite (PbFe 6 (SO 4 ) 4 (OH) 12 ) and Anglesite (PbSO 4 ) was of particular interest with respect to defining the phase(s) controlling Pb solubility. The medium contained no K + and a low level of 6.06 mM NH 4 + . Precipitates were prepared in two phases. In the first phase (8 days), A. ferrooxidans cultures oxidized ferrous iron to ferric iron (pH 2.4), which partially precipitated as schwertmannite (Fe 8 O 8 (OH) 5.5 (SO 4 ) 1.25 ). In the second phase, lead nitrate (up to 100 mmol Pb/l) was added to the schwertmannite-containing culture solutions, and the suspensions were held for an additional 22 days. X-ray diffraction analysis indicated that lead precipitated as Anglesite, and ferric iron was associated with schwertmannite and hydronium jarosite. No characteristic X-ray diffraction peaks for plumbojarosite were evident.
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Inhibition of bacterial oxidation of ferrous iron by lead nitrate in sulfate-rich systems
Journal of hazardous materials, 2012Co-Authors: Hongmei Wang, Olli H. Tuovinen, Linfeng Gong, Charles A. Cravotta, Xiaofen Yang, Hailiang DongAbstract:Abstract Inhibition of bacterial oxidation of ferrous iron (Fe(II)) by Pb(NO 3 ) 2 was investigated with a mixed culture of Acidithiobacillus ferrooxidans. The culture was incubated at 30 °C in ferrous-sulfate medium amended with 0–24.2 mM Pb(II) added as Pb(NO 3 ) 2 . Anglesite (PbSO 4 ) precipitated immediately upon Pb addition and was the only solid phase detected in the abiotic controls. Both Anglesite and jarosite (KFe 3 (SO 4 ) 2 (OH) 6 ) were detected in inoculated cultures. Precipitation of Anglesite maintained dissolved Pb concentrations at 16.9–17.6 μM regardless of the concentrations of Pb(NO 3 ) 2 added. Fe(II) oxidation was suppressed by 24.2 mM Pb(NO 3 ) 2 addition even when Anglesite was removed before inoculation. Experiments with 0–48 mM KNO 3 demonstrated that bacterial Fe(II) oxidation decreased as nitrate concentration increased. Therefore, inhibition of Fe(II) oxidation at 24.2 mM Pb(NO 3 ) 2 addition resulted from nitrate toxicity instead of Pb addition. Geochemical modeling that considered the initial precipitation of Anglesite to equilibrium followed by progressive oxidation of Fe(II) and the precipitation of jarosite and an amorphous iron hydroxide phase, without allowing plumbojarosite to precipitate were consistent with the experimental time-series data on Fe(II) oxidation under biotic conditions. Anglesite precipitation in mine tailings and other sulfate-rich systems maintains dissolved Pb concentrations below the toxicity threshold of A. ferrooxidans.
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Growth of sulfate-reducing bacteria with solid-phase electron acceptors.
Applied Microbiology and Biotechnology, 2002Co-Authors: Olga V. Karnachuk, Kurochkina Sy, Olli H. TuovinenAbstract:Hannebachite (CaSO3 x 0.5H2O), gypsum (CaSO4 x 2H2O), Anglesite (PbSO4), and barite (BaSO4) were tested as electron acceptors for sulfate-reducing bacteria with lactate as the electron donor. Hannebachite and gypsum are commonly associated with flue gas desulfurization products, and Anglesite is a weathering product found in lead mines. Barite was included as the most insoluble sulfate. Growth of sulfate-reducing bacteria was monitored by protein and sulfide (dissolved H2S and HS-) measurements. Biogenic sulfide formation occurred with all four solid phases, and protein data confirmed that bacteria grew under these electron acceptor conditions. Sulfide formation from gypsum was almost comparable in rate and quantity to that produced from soluble sulfate salt (Na2SO4); hannebachite reduction to sulfide was not as fast. Anglesite as the electron acceptor was also reduced to sulfide in the solution phase and galena (PbS) was detected in solids retrieved from spent cultures. Barite as the electron acceptor supported the least amount of growth and H2S formation. The results demonstrate that low-solubility crystalline phases can be biologically reactive under reducing conditions. Furthermore, the results demonstrate that galena precipitation through sulfide production by sulfate-reducing bacteria serves as a lead enrichment mechanism, thereby also alleviating the potential toxicity of lead. In view of the role of acidophilic thiobacilli in the oxidation of sulfides, the present work accentuates the role of anaerobic and aerobic microbes in the biogeochemical cycling of solid-phase sulfates and sulfides.
Alexandra Courtin-nomade - One of the best experts on this subject based on the ideXlab platform.
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Environmental stability and oral bioaccessibility of synthetic Pb-bearing phases to better evaluate soil health risks
Environmental science and pollution research international, 2020Co-Authors: Matthias Monneron-gyurits, Emmanuel Joussein, Marilyne Soubrand, Patrice Fondanèche, Karine Cleries, Emmanuelle Ducloux, Alexandra Courtin-nomadeAbstract:A large amount of contaminated sites is shown around the world which may induce a health risk due to the presence of contaminants such as metal (loid)s bearing phases. Health risk assessment is based on contaminant bioaccessibility. However, it is needed to understand every contaminant behavior in physiological matrix to be a realistic way to assess and interpret these sanitary risks. Due to the complexity of contaminated soil matrix, the use of synthetic minerals seems to be the better tool to understand their behavior in physiological matrix. Then, this study aims to highlight the environmental stability and the behavior during bioaccessibility ingestion (UBM) of selected synthetic lead-bearing phases. For this purpose, three Pb phases (galena, beudantite, and Anglesite) commonly found in contaminated environments (particularly mining sites) were synthesized and characterized (structurally and morphologically). The sequential BCR extractions have shown that most of the lead is in a stable and non-mobilizable form (up to 93%). The lead present in these phases represents very few risks of migrating into the environment during physicochemical condition changes. The results of the bioaccessibility revealed a relatively high stability of the pure bearing phases in the physiological matrix. Lead is stable for 97.0% to 99.2% during the gastric phase and 97.0% to 99.9% during the gastro-intestinal phase. Moreover, the synthetic mixtures of galena/beudantite and Anglesite/beudantite have been realized considering the proportions commonly found in the mining contexts. This has shown a similar behavior compared to pure phases except in the case of the Anglesite mixture inducing a clear cocktail effect (drastic increase of Pb amount from gastro-intestinal phases). At last, this study is a first and interesting step to assess the behavior of these bearing phases in heterogeneous and complex medium such as soil.
Martin Mihaljevič - One of the best experts on this subject based on the ideXlab platform.
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The pH-dependent leaching of inorganic contaminants from secondary lead smelter fly ash.
Journal of hazardous materials, 2009Co-Authors: Martina Vítková, Vojtech Ettler, Martin Mihaljevič, Ondrej Sebek, Tomás Grygar, Jan RohovecAbstract:The leaching behaviour of fly ash (FA) from a secondary Pb smelter was assessed using the pH-static leaching experiment according to prEN 14997 (pH range 3-11) coupled with mineralogical investigation of the leached FA by XRD and Rietveld analyses and thermodynamic modelling using PHREEQC-2. The procedure was performed on fresh FA and FA washed at a cumulative L/S ratio of 60l/kg to remove readily soluble salts. For both fresh and washed FA, high amounts of inorganic contaminants were released under acidic conditions, exhibiting L-shaped leaching patterns: up to 300g Pb/kg, 4.5g Cd/kg, 4g Zn/kg, 1.05g As/kg and 70mg Sb/kg. The washing of soluble salts significantly decreased the leachability of Cd, Zn, As and Sb and increased the release of Pb, especially under acidic conditions. The leaching of fresh FA removed part of primary caracolite and all the KPb(2)Cl(5) and NaCl. The Pb release was controlled by the precipitation of Anglesite and PbSO(3) under acidic conditions and of laurionite and carbonates (hydrocerussite and phosgenite) under alkaline conditions. In contrast, the washed FA was composed mainly of Anglesite and PbSO(3), both phases being the main solubility-controlling phases for Pb over the whole studied pH range.
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Metal-contaminant leaching from lead smelter fly ash using pH-stat experiments
Mineralogical Magazine, 2008Co-Authors: Martina Vítková, Vojtěch Ettler, Ondřej Šebek, Martin MihaljevičAbstract:Fly ash from secondary Pb metallurgy was submitted to the pH-static leaching procedure according to the PrEN 14997 European leaching standard. The 48 h pH-static leaching experiments were performed on (1) fresh untreated fly ash and (2) previously washed fly ash with a cumulative wash step of 60 l kg −1 . Greater release of metallic contaminants (Pb, Cd, Zn) was observed in the acidic pH range for both ashes. Washing significantly reduced the release of Cd and Zn, but greater concentrations of Pb were observed in leachates from washed fly ash due to the more important leaching of Anglesite (PbSO 4 ). The PHREEQC-2 speciation-solubility calculations showed that Anglesite, phosgenite (PbCl 2 ·PbCO 3 ) and laurionite (Pb(OH)Cl) are the most important solubility-controlling phases for Pb, which is the most important contaminant.
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Mineralogy of air-pollution-control residues from a secondary lead smelter: environmental implications.
Environmental science & technology, 2005Co-Authors: Vojtech Ettler, Zdenek Johan, Alain Baronnet, Filip Jankovsky, Christian Gilles, Martin Mihaljevič, Ondrej Sebek, Ladislav Strnad, Petr BezdičkaAbstract:The mineralogy and solubility of air-pollution-control (APC) residues from a secondary lead (Pb) smelter have been studied on samples from the Pribram smelter, Czech Republic, recycling car batteries, with the emphasis on their potential environmental effect. The presence of dominant Anglesite (PbSO 4 ) and laurionite (Pb(OH)Cl) was observed in a sintered residue from after-burning chambers (800-1000 °C). In contrast, low-temperature Pb-bearing phases, such as KCI.2PbCl 2 and caracolite (Na 3 Pb 2 (SO 4 ) 3 Cl), were detected in the major APC residue from bag-type fabric filters. Metallic elements, zinc (Zn), cadmium (Cd), and tin (Sn) were found homogeneously distributed within this residue. The formation of Anglesite, cotunnite (PbCl 2 ), (Zn,Cd) 2 SnO 4 , and (Sb,As) 2 O 3 was observed during the sintering of this APC residue at 500 °C in a rotary furnace. The 168 h leaching test on filter residue, representing the fraction that may escape the flue gas treatment system, indicated rapid release of Pb and other contaminants. Caracolite and KCl.2PbCl 2 are significantly dissolved, and Anglesite and cotunnite form the alteration products, as was confirmed by mineralogical analysis and PHREEQC-2 modeling. The observed Pb-bearing chlorides have significantly higher solubility than Anglesite and, following emission from the smelter stack, can readily dissolve, transferring Pb into the environmental milieu (soils, water, inhabited areas).
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Leaching of APC residues from secondary Pb metallurgy using single extraction tests: the mineralogical and the geochemical approach.
Journal of hazardous materials, 2005Co-Authors: Vojtech Ettler, Martin Mihaljevič, Ondrej Sebek, Ladislav StrnadAbstract:Two air-pollution-control (APC) residues--one from flue gas cooling with alkaline water and one from deionized water cooling--from secondary lead metallurgy were submitted to two different standardized short-term leaching protocols: US EPA toxicity characteristic leaching procedure (TCLP) and static leaching according to Czech/European norm EN 12457-2. The experimental procedure was coupled with detailed mineralogical investigation of the solid material (SEM, XRPD) and speciation-solubility calculations using the PHREEQC-2 geochemical code. Both types of residues were considered as hazardous materials exhibiting substantial leaching of Pb (up to 7130 mg/l) and other inorganic contaminants. However, the APC residue produced by flue gas cooling with alkaline water (sample B) exhibits more favourable leaching and environmental characteristics than that produced by simple deionised water cooling (sample A). At pH < 5, primary caracolite (Na3Pb2(SO4)3Cl) and potassium lead chloride (KCl.2PbCl2) are completely or partially dissolved and transformed to residual Anglesite (PbSO4), cotunnite (PbCl2) and laurionite (Pb(OH)Cl). At pH 5-6, Anglesite is still the principal residual product, whereas at pH > 6, phosgenite (PbCl2.PbCO3) became the dominant secondary phase. The results are consistent with the mineralogical and geochemical studies focused on acidic forest soils highly polluted by smelter emissions, where Anglesite, as a unique Pb-bearing phase, has been detected. From the technological point of view, the mixing of APC residue with alkaline water, followed by an increase in the suspension pH and equilibration with atmospheric CO2, may be used to ensure the precipitation of less soluble Pb carbonates, which are more easily recycled in the Pb recovery process in the metallurgical plant.