Register      Login
Environmental Chemistry Environmental Chemistry Society
Environmental problems - Chemical approaches
RESEARCH ARTICLE

FeII oxidation by molecular O2 during HCl extraction

Katharina Porsch A B and Andreas Kappler A C
+ Author Affiliations
- Author Affiliations

A Geomicrobiology, Center for Applied Geosciences, University of Tuebingen, Sigwartstrasse 10, D-72076 Tuebingen, Germany.

B Present address: Helmholtz Centre for Environmental Research – UFZ, Department of Bioenergy, Permoserstrasse 15, D-04318 Leipzig, Germany.

C Corresponding author. Email: andreas.kappler@uni-tuebingen.de

Environmental Chemistry 8(2) 190-197 https://doi.org/10.1071/EN10125
Submitted: 11 November 2010  Accepted: 18 February 2011   Published: 2 May 2011

Environmental context. In the environment, iron exists mainly as FeII and FeIII and plays an important role in biogeochemical processes. The FeII and FeIII content is often quantified by hydrochloric acid extraction and the acid is thought to prevent FeII oxidation by oxygen. However, we found that with increasing HCl concentration and temperature, oxidation of FeII by oxygen is accelerated. Therefore, in order to obtain reliable results extractions should be performed with dilute HCl or in the absence of oxygen.

Abstract. HCl is commonly used to stabilise FeII under oxic conditions and is often included in Fe extractions. Although FeII oxidation by molecular O2 in HCl is described in the field of hydrometallurgy, this phenomenon has not been systematically studied in environmentally relevant systems. The extent of FeII oxidation by O2 during extraction of soils and magnetite by HCl and in HCl/FeCl2 solutions was therefore quantified. FeII was stable in 1 M HCl at room temperature for several days, whereas in 6 M HCl at 70°C, 90% of the FeII was oxidised within 24 h. In the absence of O2, no FeII oxidation occurred. Experiments at low pH with increasing H+ or Cl concentration alone and geochemical modelling suggested that the formation of complexes of FeII and HCl may be responsible for the observed FeII oxidation. The use of strictly anoxic conditions for Fe extraction by HCl to obtain reliable Fe redox speciation data is therefore recommended.

Additional keywords: abiotic oxidation, biogeochemistry, geomicrobiology, iron minerals, soil extraction.


References

[1]  C. R. Myers, K. H. Nealson, Microbial reduction of manganese oxides – Interactions with iron and sulfur. Geochim. Cosmochim. Acta 1988, 52, 2727.
Microbial reduction of manganese oxides – Interactions with iron and sulfur.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1MXkt1eisw%3D%3D&md5=41160cd4a7ab5bf83ff1ec5d6cffab16CAS |

[2]  J. T. Moraghan, R. J. Buresh, Chemical reduction of nitrite and nitrous-oxide by ferrous iron. Soil Sci. Soc. Am. J. 1977, 41, 47.
Chemical reduction of nitrite and nitrous-oxide by ferrous iron.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE2sXhvVynsr4%3D&md5=2ec91a31cf241ea75b7f5e7aed6ebd3bCAS |

[3]  W. Stumm, G. F. Lee, Oxygenation of ferrous iron. Ind. Eng. Chem. 1961, 53, 143.
Oxygenation of ferrous iron.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaF3MXnslymsQ%3D%3D&md5=0f18962b055f009cb9f632089d748a22CAS |

[4]  W. Stumm, J. J. Morgan, Aquatic Chemistry: Chemical Equilibria and Rates in Natural Waters 1996 (Wiley: New York).

[5]  M. dos Santos Afonso, W. Stumm, Reductive dissolution of iron(III) (hydr)oxides by hydrogen sulfide. Langmuir 1992, 8, 1671.
Reductive dissolution of iron(III) (hydr)oxides by hydrogen sulfide.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK38XktFGisbg%3D&md5=4c9fcb8b0de32c4f85c1a3b91e6e5d64CAS |

[6]  I. Bauer, A. Kappler, Rates and extent of reduction of FeIII compounds and O2 by humic substances. Environ. Sci. Technol. 2009, 43, 4902.
Rates and extent of reduction of FeIII compounds and O2 by humic substances.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXmtVGntLk%3D&md5=747f78cb49e199dec7c407572200fae4CAS | 19673283PubMed |

[7]  K. A. Weber, L. A. Achenbach, J. D. Coates, Microorganisms pumping iron: Anaerobic microbial iron oxidation and reduction. Nat. Rev. Microbiol. 2006, 4, 752.
Microorganisms pumping iron: Anaerobic microbial iron oxidation and reduction.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XpsFOktLg%3D&md5=f9bae26c1da2c359f5438b060462df77CAS | 16980937PubMed |

[8]  C. Schmidt, S. Behrens, A. Kappler, Ecosystem functioning from a geomicrobiological perspective – a conceptual framework for biogeochemical iron cycling. Environ. Chem. 2010, 7, 399.
Ecosystem functioning from a geomicrobiological perspective – a conceptual framework for biogeochemical iron cycling.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXhsFChsrfK&md5=d72eb2949a1b537dc9a112a38c253026CAS |

[9]  T. Borch, Y. Masue, R. K. Kukkadapu, S. Fendorf, Phosphate imposed limitations on biological reduction and alteration of ferrihydrite. Environ. Sci. Technol. 2007, 41, 166.
Phosphate imposed limitations on biological reduction and alteration of ferrihydrite.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XhtlCit7jF&md5=3be5b7dff2f5ae9d4160d17b842c2770CAS | 17265943PubMed |

[10]  J. M. Zachara, R. K. Kukkadapu, J. K. Fredrickson, Y. A. Gorby, S. C. Smith, Biomineralization of poorly crystalline FeIII oxides by dissimilatory metal reducing bacteria (DMRB). Geomicrobiol. J. 2002, 19, 179.
Biomineralization of poorly crystalline FeIII oxides by dissimilatory metal reducing bacteria (DMRB).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XjslGrsbc%3D&md5=4fdbd3bd54b1c7a8a7703834c35204c9CAS |

[11]  J. K. Fredrickson, J. M. Zachara, D. W. Kennedy, H. Dong, T. C. Onstott, N. W. Hinman, S.-M. Li, Biogenic iron mineralization accompanying the dissimilatory reduction of hydrous ferric oxide by a groundwater bacterium. Geochim. Cosmochim. Acta 1998, 62, 3239.
Biogenic iron mineralization accompanying the dissimilatory reduction of hydrous ferric oxide by a groundwater bacterium.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1MXitlGlsLw%3D&md5=29cfcc11ee8ef472f74bc0aabcd20a14CAS |

[12]  C. M. Hansel, S. G. Benner, S. Fendorf, Competing FeII-induced mineralization pathways of ferrihydrite. Environ. Sci. Technol. 2005, 39, 7147.
Competing FeII-induced mineralization pathways of ferrihydrite.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXotFSit7w%3D&md5=3ed54679f0b81706bda02be4aac7e7f5CAS | 16201641PubMed |

[13]  K. Eusterhues, F. E. Wagner, W. Häusler, M. Hanzlik, H. Knicker, K. U. Totsche, I. Kögel-Knabner, U. Schwertmann, Characterization of ferrihydrite-soil organic matter coprecipitates by X-ray diffraction and Mössbauer spectroscopy. Environ. Sci. Technol. 2008, 42, 7891.
Characterization of ferrihydrite-soil organic matter coprecipitates by X-ray diffraction and Mössbauer spectroscopy.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXht1Wjsr7F&md5=9a0e244b9719ae871459d9f208897a84CAS | 19031877PubMed |

[14]  C. Hohmann, E. Winkler, G. Morin, A. Kappler, Anaerobic FeII-oxidizing bacteria show As resistance and immobilize As during FeIII mineral precipitation. Environ. Sci. Technol. 2010, 44, 94.
Anaerobic FeII-oxidizing bacteria show As resistance and immobilize As during FeIII mineral precipitation.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXhtFKktL3E&md5=4fcc3fb46e0be538d3886de29889b55fCAS | 20039738PubMed |

[15]  F. S. Islam, A. G. Gault, C. Boothman, D. A. Polya, J. M. Charnock, D. Chatterjee, J. R. Lloyd, Role of metal-reducing bacteria in arsenic release from Bengal delta sediments. Nature 2004, 430, 68.
Role of metal-reducing bacteria in arsenic release from Bengal delta sediments.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXlt1Cqt7c%3D&md5=9d36eb3fc8affbfaf27a57e8f82f01f9CAS | 15229598PubMed |

[16]  K. Amstaetter, T. Borch, P. Larese-Casanova, A. Kappler, Redox transformation of arsenic by FeII-activated goethite (α-FeOOH). Environ. Sci. Technol. 2010, 44, 102.
Redox transformation of arsenic by FeII-activated goethite (α-FeOOH).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXht1artbrI&md5=5b81f022a95008e042482127c017f573CAS | 20039739PubMed |

[17]  G. G. Geesey, A. L. Neal, P. A. Suci, B. M. Peyton, A review of spectroscopic methods for characterizing microbial transformations of minerals. J. Microbiol. Methods 2002, 51, 125.
A review of spectroscopic methods for characterizing microbial transformations of minerals.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XlsVOrsr4%3D&md5=7b0a20b566264808ef089acb88694980CAS | 12133605PubMed |

[18]  G. Heron, C. Crouzet, A. C. M. Bourg, T. H. Christensen, Speciation of FeII and FeIII in contaminated aquifer sediments using chemical extraction techniques. Environ. Sci. Technol. 1994, 28, 1698.
Speciation of FeII and FeIII in contaminated aquifer sediments using chemical extraction techniques.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXltFKqtLk%3D&md5=dbe55b84ff314637c64c499869da1ce5CAS |

[19]  S. W. Poulton, D. E. Canfield, Development of a sequential extraction procedure for iron: Implications for iron partitioning in continentally derived particulates. Chem. Geol. 2005, 214, 209.
Development of a sequential extraction procedure for iron: Implications for iron partitioning in continentally derived particulates.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXkvVCjsg%3D%3D&md5=9d37c0ffb99726d13805789865c38282CAS |

[20]  K. Wallmann, K. Hennies, I. König, W. Petersen, H. D. Knauth, New procedure for determining reactive FeIII and FeII minerals in sediments. Limnol. Oceanogr. 1993, 38, 1803.
New procedure for determining reactive FeIII and FeII minerals in sediments.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2cXlvVKlsrw%3D&md5=37ff40b91150bc931133823596ae697fCAS |

[21]  D. R. Lovley, E. J. P. Phillips, Rapid assay for microbially reducible ferric iron in aquatic sediments. Appl. Environ. Microbiol. 1987, 53, 1536..
| 16347384PubMed |

[22]  E. E. Roden, J. M. Zachara, Microbial reduction of crystalline iron(III) oxides: Influence of oxide surface area and potential for cell growth. Environ. Sci. Technol. 1996, 30, 1618.
Microbial reduction of crystalline iron(III) oxides: Influence of oxide surface area and potential for cell growth.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK28XhvVKgt7k%3D&md5=3a9f4bdf7d96111df08efb0522a967acCAS |

[23]  Y. Awakura, M. Iwai, H. Majima, Oxidation of FeII in HCl and H2SO4 solutions with dissolved oxygen in the presence and absence of a cupric catalyst, in Iron Control in Hydrometallurgy (Eds J. E. Dutrizac, A. J. Monhemius) 1986, pp. 202–222 (Ellis Horwood Limited: Chichester).

[24]  M. Iwai, H. Majima, T. Izaki, Kinetic study on the oxidation of ferrous ion with dissolved molecular-oxygen. Denki Kagaku 1979, 47, 409..

[25]  A. M. Posner, The kinetics of autoxidation of ferrous ions in concentrated HCl solutions. Trans. Faraday Soc. 1953, 49, 382.
The kinetics of autoxidation of ferrous ions in concentrated HCl solutions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaG3sXntVGqsQ%3D%3D&md5=83f75b4fc0e6ce08fc9634c67f9fa349CAS |

[26]  L. L. Stookey, Ferrozine – a new spectrophotometric reagent for iron. Anal. Chem. 1970, 42, 779.
Ferrozine – a new spectrophotometric reagent for iron.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE3cXkt1WjtL8%3D&md5=fd4d96a3cb67ba57e0c96cd099e2b0baCAS |

[27]  F. Hegler, N. R. Posth, J. Jiang, A. Kappler, Physiology of phototrophic iron(II)-oxidizing bacteria: Implications for modern and ancient environments. FEMS Microbiol. Ecol. 2008, 66, 250.
Physiology of phototrophic iron(II)-oxidizing bacteria: Implications for modern and ancient environments.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXhtlyqsrjM&md5=d77c106691fc4309b6e481f94fb7adddCAS | 18811650PubMed |

[28]  J. Weiss, Electron transition process in the mechanism of oxidation and reduction reactions in solutions. Naturwissenschaften 1935, 23, 64.
Electron transition process in the mechanism of oxidation and reduction reactions in solutions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaA2MXjtVaitQ%3D%3D&md5=629358b65f35577f007608cc535b848bCAS |

[29]  F. J. Millero, The effect of ionic interactions on the oxidation of metals in natural waters. Geochim. Cosmochim. Acta 1985, 49, 547.
The effect of ionic interactions on the oxidation of metals in natural waters.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2MXhtFOjtrs%3D&md5=6b4ee04452db24c166b55eb5af9300edCAS |

[30]  H. Tamura, K. Goto, M. Nagayama, Effect of anions on oxygenation of ferrous ion in neutral solutions. J. Inorg. Nucl. Chem. 1976, 38, 113.
Effect of anions on oxygenation of ferrous ion in neutral solutions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaE28Xps1Sntg%3D%3D&md5=db81872807b7ddba8bfaa7528f215e59CAS |

[31]  J. M. Trapp, F. J. Millero, The oxidation of iron(II) with oxygen in NaCl brines. J. Solution Chem. 2007, 36, 1479.
The oxidation of iron(II) with oxygen in NaCl brines.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXhtlKmtrrK&md5=a0f05c6413bd70298be0c0ff51745009CAS |

[32]  R. Zhao, P. Pan, A spectrophotometric study of FeII-chloride complexes in aqueous solutions from 10 to 100°C. Can. J. Chem. 2001, 79, 131.
A spectrophotometric study of FeII-chloride complexes in aqueous solutions from 10 to 100°C.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXislWnsL0%3D&md5=aceeff9f3b3fa635a4e34e341af417efCAS |

[33]  C. A. Heinrich, T. M. Seward, A spectrophotometric study of aqueous iron(II) chloride complexing from 25 to 200°C. Geochim. Cosmochim. Acta 1990, 54, 2207.
A spectrophotometric study of aqueous iron(II) chloride complexing from 25 to 200°C.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3cXlsFKisrg%3D&md5=21edd9a1fd8179d02c2cbb9ee9d0c9fbCAS |

[34]  M. S. Lee, Use of the Bromley equation for the analysis of ionic equilibria in mixed ferric and ferrous chloride solutions at 25°C. Metall. Mater. Trans. B 2006, 37, 173.
Use of the Bromley equation for the analysis of ionic equilibria in mixed ferric and ferrous chloride solutions at 25°C.Crossref | GoogleScholarGoogle Scholar |

[35]  A. N. Astanina, A. P. Rudenko, Effect of acids on homogenous oxidation of iron(II) by molecular oxygen in aqueous solution. Russ. J. Phys. Chem. 1971, 45, 194.

[36]  S. K. Chaudhuri, J. G. Lack, J. D. Coates, Biogenic magnetite formation through anaerobic biooxidation of FeII. Appl. Environ. Microbiol. 2001, 67, 2844.
Biogenic magnetite formation through anaerobic biooxidation of FeII.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXkt1Citbk%3D&md5=25201702183180aff1867cc3320a0a4eCAS | 11375205PubMed |

[37]  A. Kappler, D. K. Newman, Formation of FeIII-minerals by FeII-oxidizing photoautotrophic bacteria. Geochim. Cosmochim. Acta 2004, 68, 1217.
Formation of FeIII-minerals by FeII-oxidizing photoautotrophic bacteria.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhvVGhsb8%3D&md5=1ad23de665e008c07a905b9f81abea53CAS |

[38]  A. Matthews, X.-K. Zhu, K. O’Nions, Kinetic iron stable isotope fractionation between iron(-II) and (-III) complexes in solution. Earth Planet. Sci. Lett. 2001, 192, 81.
Kinetic iron stable isotope fractionation between iron(-II) and (-III) complexes in solution.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXnt1Sjsbc%3D&md5=26073f1e4beaa51b223876ca4fdfcf7eCAS |