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57 results on '"Ferrous iron oxidation"'

51. Complete Genome Sequence of Acidithiobacillus Ferrooxidans YNTRS-40, a Strain of the Ferrous Iron- and Sulfur-Oxidizing Acidophile.

Author

Zhang Y, Zhang S, Zhao D, Ni Y, Wang W, and Yan L

Abstract

Acidithiobacillus ferrooxidans YNTRS-40 ( A. ferrooxidans ) is a chemolithoautotrophic aerobic bacterium isolated from Tengchong hot springs, Yunnan Province, China, with a broad growth pH range of 1.0-4.5. This study reports the genome sequence of this strain and the information of genes related to the adaptation of diverse stresses and the oxidation of ferrous iron and sulfur. Results showed that YNTRS-40 possesses chromosomal DNA (3,209,933-bp) and plasmid DNA (47,104-bp). The complete genome of 3,257,037-bp consists of 3,349 CDS genes comprising 6 rRNAs, 52 tRNAs, and 6 ncRNAs. There are many encoded genes associated with diverse stresses adaptation and ferrous iron and sulfur oxidation such as rus operon, res operon, petI , petII , sqr , doxDA , cydAB , and cyoABCD . This work will provide essential information for further application of A. ferrooxidans YNTRS-40 in industry.

Published
2019
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52. High-rate iron oxidation at below pH 1 and at elevated iron and copper concentrations by a Leptospirillum ferriphilum dominated biofilm

Author

Jaakko A. Puhakka and Päivi Kinnunen

Subjects
High rate, biology, Chemistry, Leptospirillum ferriphilum, Inorganic chemistry, Biofilm, chemistry.chemical_element, Bioengineering, biology.organism_classification, Applied Microbiology and Biotechnology, Biochemistry, Copper, Enrichment culture, Ferrous, Metal tolerance, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Loading rate, medicine, Ferric, medicine.drug, Ferrous iron oxidation
Abstract

The influences of H+, Fe2+, Fe3+ and Cu2+ ion concentrations and their different combinations on the iron oxidation by an enrichment culture dominated by Leptospirillum ferriphilum were studied in batch experiments and continuous-flow fluidized-bed reactors. The iron oxidation rate did not significantly vary in the pH range of 0.9-1.5 and was only partially inhibited at pH 0.7. Ferric and ferrous iron at 5 and 24 g L-1, respectively, had little or no effect on iron oxidation by the enrichment culture and the iron oxidation rate slightly decreased at higher concentrations. At a loading rate of 3 g Fe2+ L-1 h -1, 2 g L-1 Cu2+ did not affect the iron oxidation rate, whereas at a loading rate of 10 g Fe2+ L-1 h-1 it reduced the rate by 69%. The maximum iron oxidation rate was 10 g Fe2+ L-1 h-1 at pH 0.9 and in the presence of 21 g L-1 Fe2+ and 2 g L-1 Cu2+.

Published
2005

53. Sorption and catalytic oxidation of Fe(II) at the surface of calcite

Author

Laurent Charlet, Urs von Gunten, Suzanne Mettler, Mariette Wolthers, Swiss Federal Insitute of Aquatic Science and Technology [Dübendorf] (EAWAG), Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Laboratoire Central des Ponts et Chaussées (LCPC)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Faculty of Geosciences, UCEL, Utrecht University [Utrecht], funding by KTI, partial funding by RECOSY, partial funding by ANDRA and VENI grant #016.071.018 of NWO, ANR-05-PCO2-0009,Geocarbone-CARBONATATION,[Bio]Minéralisation du carbone: de la caractérisation expérimentale à la modélisation(2005), Eidgenössische Anstalt für Wasserversorgung, Abwasserreinigung und Gewässerschutz (Eawag) (EAWAG), Swiss Federal Institute of Aquatic Science and Technology, Dubendorf, Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Laboratoire Central des Ponts et Chaussées (LCPC)-Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), and ANR Geocarbone-Carbonation,ANR Geocarbone-Carbonation

Subjects
Precipitation Model, Coprecipitation, Aardwetenschappen, Natural-Waters, Inorganic chemistry, 0207 environmental engineering, 02 engineering and technology, 010501 environmental sciences, 01 natural sciences, Ferrous Iron, chemistry.chemical_compound, Adsorption, iron, surface adsorption and precipitation model, Geochemistry and Petrology, Metal Sorption, Ground-Water, 020701 environmental engineering, Carbonates Solution Interface, Dissolution, surface complexation model, 0105 earth and related environmental sciences, Carbonic acid, Calcite, sorption, Aquatic Systems, Sorption, Ionic Interactions, Organic-Matter, chemistry, Catalytic oxidation, Chlorine Dioxide, ferrous iron oxidation, Carbonate, calcite, heterogeneous oxidation
Abstract

The effect of sorption and coprecipitation of Fe(II) with calcite on the kinetics of Fe(II) oxidation was investigated. The interaction of Fe(II) with calcite was studied experimentally in the absence and presence of oxygen. The sorption of Fe(II) on calcite occurred in two distinguishable steps: (a) a rapid adsorption step (seconds-minutes) was followed by (b) a slower incorporation (hours-weeks). The incorporated Fe(II) could not be remobilized by a strong complexing agent (phenanthroline or ferrozine) but the dissolution of the outmost calcite layers with carbonic acid allowed its recovery. Based on results of the latter dissolution experiments, a stoichiometry of 0.4 mol% Fe:Ca and a mixed carbonate layer thickness of 25 nm (after 168 It equilibration) were estimated. Fe(II) sorption on calcite could be successfully described by a surface adsorption and precipitation model (Comans & Middelburg, GCA 51 (1987), 2587) and surface complexation modeling (Van Cappellen et al., GCA 57 (1993), 3505; Pokrovsky et al., Langmuir 16 (2000), 2677). The surface complex model required the consideration of two adsorbed Fe(II) surface species, >CO3Fe+ and >CO3FeCO3H0. For the formation of the latter species, a stability constant is being suggested. The oxidation kinetics of Fe(II) in the presence of calcite depended on the equilibration time of aqueous Fe(II) with the mineral prior to the introduction of oxygen. If pre-equilibrated for >15 h, the oxidation kinetics was comparable to a calcite-free system (t(1/2) = 145 +/- 15 min). Conversely, if Fe(II) was added to an aerated calcite suspension, the rate of oxidation was higher than in the absence of calcite (t(1/2) = 41 +/- 1 min and t(1/2) = 100 +/- 15 min, respectively). This catalysis was due to the greater reactivity of the adsorbed Fe(II) species, >CO3FeCO3H0, for which the species specific rate constant was estimated. (c) 2009 Elsevier Ltd. All rights reserved.

Published
2009

55. Effect of chloride on ferrous iron oxidation by a leptospirillum ferriphilum-dominated chemostat culture

Author

Gahan, CS, Sundkvist, JE, Dopson, Mark, Sandström, A, Gahan, CS, Sundkvist, JE, Dopson, Mark, and Sandström, A

Abstract

Biomining is the use of microorganisms to catalyze metal extraction from sulfide ores. However, the available water in some biomining environments has high chloride concentrations and therefore, chloride toxicity to ferrous oxidizing microorganisms has been investigated. Batch biooxidation of Fe2+ by a Leptospirillum ferriphilum dominated culture was completely inhibited by 12gL(-1) chloride. In addition, the effects of chloride on oxidation kinetics in a Fe2+ limited chemostat were studied. Results from the chemostat modeling suggest that the chloride toxicity was attributed to affects on the Fe2+ oxidation system, pH homeostasis, and lowering of the proton motive force. Modeling showed a decrease in the maximum specific growth rate (mu(max)) and an increase in the substrate constant (K-s) with increasing chloride concentrations, indicating an effect on the Fe2+ oxidation system. The model proposes a lowered maintenance activity when the media was fed with 2-3 g L-1 chloride with a concomitant drastic decrease in the true yield (Y-true). This model helps to understand the influence of chloride on Fe2+ biooxidation kinetics. Biotechnol. Bioeng. 2010;106: 422-431. (C) 2010 Wiley Periodicals, Inc.

Published
2010
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57. Microbial Fe(II)-oxidation by nitrate in activated sludge

Author

Nielsen, P. H. and Nielsen, J. L.

Subjects
*DENITRIFICATION, *ACTIVATED sludge process, *WASTEWATER treatment
Abstract

The oxidation of Fe(II) to Fe(III) by addition of nitrate and nitrite to activated sludge was studied to determine whether the process was biological or chemical (chemodenitrification). It was shown that the process was mainly biological, although the microorganisms involvedhave not yet been described. Investigations in a full scale treatment plant suggested that the process most likely took place in the anoxic (denitrification) tank. Details of the kinetics and stoichiometry have not yet been determined, but the process may he of significance for keeping Fe(III) oxidized, which is important for P-removal and for floc structure. Furthermore, in some treatment plants, the oxidation may also be of significance for nitrate removal (denitrification). ) 1998 IAWQ. Published by Elsevier Science Ltd. [ABSTRACT FROM AUTHOR]

Published
1998
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