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  • 1.
    Antzutkin, Oleg
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Kota, Hanumantha Rao
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ikumapayi, Fatai
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Holmgren, Allan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Johansson, Björn
    New Boliden AB.
    Berggren, Andreas
    New Boliden AB.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Öberg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Hedlund, Jonas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Mouzon, Johanne
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Bhuiyan, Iftekhar Uddin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsmo, Seija
    LKAB.
    Interactions in multi-component mineral systems2011Conference paper (Other academic)
    Download full text (pdf)
    fulltext
  • 2. Gunneriusson, Lars
    Aqueous speciation and surface complexation to goethite (α-FeOOH), of divalent mercury, lead and cadmium1993Doctoral thesis, comprehensive summary (Other academic)
  • 3. Gunneriusson, Lars
    Composition and stability of Cd(II)-chloro and -hydroxo complexes at the goethite (α-FeOOH)/water interface1994In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 163, no 2, p. 484-492Article in journal (Refereed)
    Abstract [en]

    The surface complexation of Cd(II) to goethite (α-FeOOH) in the absence and presence of chloride has been investigated. Equilibrium measurements have been performed as potentiometric titrations at 298.2 K, within the range 2.7 < -log[H+] < 9.0, in 0.1 mol dm-3 NaNO3, NaCl, and a mixture (1:1) of both these media. The data were evaluated according to the electrostatic constant capacitance model, including a previously determined model for the acid-base reactions of the goethite surface. The following model is presented (errors ± 3σ): equivalent FeOH + Cd2+ <=> equivalent FeOHCd2+; log β0,1,1,0s(int) = 6.43 ± 0.05; equivalent FeOH + Cd2+ <=> equivalent FeOCd+ + H+; log β-1,1,1,0s(int) = -2.22 ± 0.05; equivalent FeOH + Cd2+ + H2O <=> equivalent FeOCdOH + 2H+; log β-2,1,1,0s(int) = -12.01 ± 0.08; equivalent FeOH + Cd2+ + Cl- <=> equivalent FeOHCdCl+; log β0,1,1,1s(int) = 6.85 ± 0.02; equivalent FeOH + Cd2+ + Cl- <=> equivalent FeOCdCl + H+; log β-1,1,1,1s(int) = -2.38 ± 0.04. In the presence of excess Cd(II) ions to surface hydroxyl groups, it was found that the results could be explained by including bulk precipitation of Cd(OH)2. The calculated formation constant for Cd(OH)2 (s) was within an order of magnitude from the literature value for the stable phase in solution, β-Cd(OH)2. Modeling of natural water conditions showed that relatively high concentrations of goethite have to be present to influence the concentrations of Cd(II). Furthermore, the reactions were found to be nearly fully reversible, which means that adsorbed Cd(II) can be released to the environment by a relatively moderate lowering of pH

  • 4.
    Gunneriusson, Lars
    et al.
    Departments of Inorganic Chemistry, University of Umeå, Umeå, Sweden.
    Baxter, Douglas
    Departments of Analytical Chemistry, University of Umeå, Umeå, Sweden.
    Emteborg, Håkan
    Departments of Analytical Chemistry, University of Umeå, Umeå, Sweden.
    Complexation at low concentrations of methyl and inorganic mercury(II) to a hydrous goethite (α-FeOOH) surface1995In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 169, no 2, p. 262-266Article in journal (Refereed)
    Abstract [en]

    Surface complexation of inorganic mercury(II) and monomethyl mercury (CH3Hg+) onto a hydrous goethite (α-FeOOH) surface has been studied. The ph (-log[H+]) has been varied within the range 2.7 < -log[H+] < 9, at 298 K, using a 0.1 mol dm-3 NaNO3 medium. Low total mercury concentrations (≈ 1 μmol dm-3) were used. Inorganic mercury and methyl mercury content in the water phase, in the goethite phase, and adsorbed on the vessel walls was determined by GFAAS and GC-coupled MIP-AES. The inorganic mercury distribution was evaluated, using a previously determined surface complexation model, based on the constant capacitance concept. This model was derived using about 103 times higher total mercury concentrations. In the presence of goethite, approximately 80% of both methyl mercury and inorganic mercury(II) was recovered in the different phases. The extractable fraction adsorbed to the vessel walls was found to be low. About 20% of the inorganic mercury added remained soluble in the presence of goethite. This is close to the predicted value, using a previously determined model derived in the mmol dm-3 range. This implies that the concept of specific high affinity sites is questionable in the case of near trace concentrations of Hg(II). Methyl mercury was found to be weakly coordinated, with about 15% adsorbed on the goethite surface. Furthermore, a model calculation describing the surface complexation of methyl mercury on goethite was performed. The experimental data could best be explained by the formation of the surface complexes ≡FeOHHgCH+3 and ≡FeOHgCH3.

  • 5. Gunneriusson, Lars
    et al.
    Lövgren, Lars
    Sjöberg, Staffan
    Complexation of Pb(II) at the goethite (α-FeOOH)/water interface: the influence of chloride1994In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 58, no 22, p. 4973-4983Article in journal (Refereed)
  • 6.
    Gunneriusson, Lars
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Sandström, Åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Holmgren, Allan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Kuzmann, Ernő
    Laboratory of Nuclear Chemistry, Institute of Chemistry, Eötvös Loránd University.
    Kovacs, Krisztina
    Laboratory of Nuclear Chemistry, Institute of Chemistry, Eötvös Loránd University.
    Vertes, Attila
    Laboratory of Nuclear Chemistry, Institute of Chemistry, Eötvös Loránd University.
    Jarosite inclusion of fluoride and its potential significance to bioleaching of sulphide minerals2009In: Hydrometallurgy, ISSN 0304-386X, E-ISSN 1879-1158, Vol. 96, no 1-2, p. 108-116Article in journal (Refereed)
    Abstract [en]

    Incorporation of fluoride ions into the structure of jarosite, a common precipitate in bioleaching, was studied. Crystalline jarosite was synthesized in the presence of various concentrations of fluoride ions and characterized by spectroscopic- and chemical analysis.The results showed that substantial amounts of fluoride were sorbed to jarosite, increasing with pH and fluoride concentration. FTIR, XRD and Mössbauer analysis supported a structural incorporation of the fluoride. Due to the size similarity between fluoride and hydroxide ions, a probable mechanism is an exchange of hydroxide ions and fluoride ions within the jarosite, giving the composition KFe3(SO4)2(OH)6 - xFx(s). For the maximum concentration of fluoride used during synthesis, 200 mM, about 25% of the hydroxide ions were exchanged for fluoride ions. The mass of jarosite precipitated shown to be highly dependent on the fluoride concentration, with approximately half the yield using 200 mM potassium fluoride compared to in the absence of fluoride ions.To test the influence on toxicity of the incorporation of fluoride in jarosite, a bioleaching study was performed at 65 °C. A suspension of pyrite concentrate with 4% solid content (w/v) in the modified 9 K medium was bioleached under additions of potassium fluoride. The results indicated a higher tolerance for fluoride ions, as compared to earlier reported studies on fluoride toxicity during bioleaching.

  • 7. Gunneriusson, Lars
    et al.
    Sjöberg, Staffan
    Equilibrium Speciation Models for Hg, Cd, and Pb in the Gulf of Bothnia and its Catchment Area1991In: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694, Vol. 22, no 1, p. 67-80Article in journal (Refereed)
  • 8. Gunneriusson, Lars
    et al.
    Sjöberg, Staffan
    Surface Complexation in the H+-Goethite (α-FeOOH)-Hg (II)-Chloride System1993In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 156, no 1, p. 121-128Article in journal (Refereed)
  • 9.
    Jarlbring, Mathias
    et al.
    Luleå University of Technology.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsling, Willis
    Luleå University of Technology.
    Characterisation of the protolytic properties of synthetic carbonate free fluorapatite2005In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 285, no 1, p. 206-211Article in journal (Refereed)
    Abstract [en]

    The acid/base surface properties of carbonate free fluorapatite (Ca5(PO4)3F) have been characterised using high precision potentiometric titrations and surface complex modelling. Synthetic carbonate free fluorapatite was prepared and characterised by SEM, XRD, FT-IR and FT-Raman. The specific surface area was determined to be 17.7±1.2 m2g-1 with BET (N2 adsorption). The titrations were performed at 25±0.2°C, within the pH range 5.7-10.8, in 0.10 and 0.50 mol dm-3 NaNO3 ionic media. Experimental data were interpreted using the constant capacitance model and the software FITEQL 4.0. The surface equilibria:

    ≡S1OH ⇄ ≡S1O- + H+ lgβs-110 (int),

    ≡S2OH ⇄ ≡S2O- + H+ lgβs-101 (int)

    well describes the surface characteristics of synthetic fluorapatite. The equilibrium constants obtained were: lgβs-110(int)=-6.33±0.05 and lgβ-101s(int)=-8.82±0.06 at I=0.10 mol dm-3. At the ionic strength 0.50 mol dm-3, the equilibrium constants were slightly shifted to: lgβs-110(int)=-6.43±0.05 and lgβs-101(int)=-8.93±0.06. The number of active surface sites, Ns, was calculated from titration data and was found to be 2.95 and 2.34 sites nm-2 for the ionic strengths 0.10 and 0.50 mol dm-3, respectively. pHPZC or the IEP was found to be 5.7 from Z-potential measurements.

  • 10.
    Jarlbring, Mathias
    et al.
    Luleå University of Technology.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsling, Willis
    Luleå University of Technology.
    Protolytic Surface Reactions of a Fluorapatite-Maghemite Mixture in Aqueous Suspension2005In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 21, no 17, p. 7717-7721Article in journal (Refereed)
    Abstract [en]

    Synthetically prepared maghemite and fluorapatite, characterized with BET, SEM, XRD, FT-IR, and FT-Raman, are used to investigate the protolytic properties and surface characteristics in a mixed system of maghemite and fluorapatite by means of potentiometric titrations and surface complex modeling. Titrations were performed in the pH range of 7.3−10.5 at 25 ± 0.2 °C in ionic media of 0.10 mol dm-3 NaNO3 with 0.0100 mol dm-3 HNO3 and 0.0100 mol dm-3 NaOH used as titrants. The constant capacitance model (CCM) was applied to interpret the titration data. Two models with different surface equilibria were tested. In the first model, the mixed system was treated as a one-component system with a total surface area of 40.04 ± 5.2 m2 g-1 without any consideration to the subsystems. The surface equilibria, ⋮XOH + H+ ⇌ ⋮XOH2+, lg (int) = 6.74 ± 0.07; ⋮XOH ⇌ ⋮XO- + H+, lg (int) = −7.75 ± 0.07, were found to represent an accurate model for the system, and the specific capacitance was optimized to 2.0 F m-2. The number of active surface sites Ns was found to be 1.2 sites nm-2. This model has, however, no relation to the subsystems of maghemite and fluorapatite. The second model is related to the subsystems and displays the surface equilibria, ⋮S2OH ⇌ ⋮S2O- + H+, lg (int) = −9.12 ± 0.01; ⋮FeOH + H+ ⇌ ⋮FeOH2+, lg (int) = 6.80 ± 0.01; ⋮FeOH ⇌ ⋮FeO- + H+, lg (int) = −7.77 ± 0.01, where ⋮S2OH is related to fluorapatite and ⋮FeOH is representing maghemite. Fluorapatite corresponds to the dominating active surface in the system. The specific capacitance was optimized to 18 F m-2. The Ns values were found to be 2.27 sites nm-2 for fluorapatite and 0.80 sites nm-2 for maghemite. The Ns values together with evidence from the FT-Raman and SEM investigations reveal that interactions between maghemite and fluorapatite surfaces occur during the titration. The acid-base properties and surface characteristics of the subsystems maghemite−H+ and fluorapatite−OH- using the CCM have been published earlier.

  • 11.
    Jarlbring, Mathias
    et al.
    Luleå University of Technology.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Hussmann, Björn
    Technische Universität Hamburg-Harburg, Germany.
    Forsling, Willis
    Luleå University of Technology.
    Surface complex characteristics of synthetic maghemite and hematite in aqueous suspensions2005In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 285, no 1, p. 212-217Article in journal (Refereed)
    Abstract [en]

    The acid-base properties of the maghemite (γ-Fe2O3)/water and hematite (α-Fe2O3)/water interfaces have been studied by means of high precision potentiometric titrations and the experimental results are evaluated as surface complexation reactions. Synthetic maghemite and hematite were prepared and characterized using a combination of SEM, FT-IR and XRD. The specific surface area of the minerals was determined by the BET method. The titrations were performed at 25.0± 0.2°C within the range 2.8 < pH < 8.5 NaNO3 ionic medium giving total ionic strengths of 0.10 and 0.50 mol dm-3 in both systems. Experimental data were evaluated using the constant capacitance model. The total proton exchange capacities of the solids were determined by saturation of the surfaces with excess acid. The number of protonated surface sites per nm2 was found to be 0.81 ± 0.05 and 1.03 ± 0.04 for maghemite, at I = 0.10 and 0.50 mol dm-3, respectively. The IEP for maghemite was determined from the ζ-potential using a Zetasizer 4 instrument.

  • 12.
    Jolsterå, Rickard
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsling, Willis
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Adsorption and surface complex modeling of silicates on maghemite in aqueous suspensions2010In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 342, no 2, p. 493-498Article in journal (Refereed)
    Abstract [en]

    Adsorption of soluble silicate species, (Si(OH)4) on maghemite, (γ-Fe2O3) has been studied by high precision potentiometric titrations, spectroscopic analyses and zeta potential determinations. Titrations were performed at 25.0 °C within the range 2.8 < pH < 11.1 and at a constant ionic strength of 0.100 mol dm-3. The experimental data were evaluated using the constant capacitance model. For the maghemite - H+ system, the following values for the surface complexation constants and capacitance were found: ≡FeOH + H+ ↔ ≡FeOH2+; log βs11(int) = 5.39 ± 0.01 ≡FeOH ↔ ≡FeO- + H+; log βs-11(int) = -7.51 ± 0.01; C = 2.40 Fm-2.Three different concentration ratios of the determined concentration of active surface sites and added total silicate concentration, [≡FeOH]:[Si(OH)4], were examined (1:1, 2:1 and 3:1). A model comprising of three surface complexes, ≡FeOSi(OH)3, log βs011(int) = 3.61 ± 0.02; ≡FeOSiO(OH)2-, log βs-111(int) = -3.00 ± 0.01; and ≡FeOSiO2(OH)2-, log βs-211(int) = -11.35 ± 0.02; was found to best describe the experimental observations. Attempts to model the adsorption of silicates on maghemite as bidentate or polynuclear silicate complexes were not successful. The maximum silicate adsorption for the 1:1 ratio, approximately 80%, was obtained at pH 9 - 9.5. The IEP of maghemite in the presence of silicates (1:1 ratio) was determined from ζ-potential measurements, giving pHIEP ≈ 6.6.

  • 13.
    Jolsterå, Rickard
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsling, Willis
    Surface characterisation and modelling of olivine at alkaline conditions2010In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 74, no 12/Suppl 1, p. A477-Article in journal (Other academic)
  • 14.
    Jolsterå, Rickard
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Holmgren, Allan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Surface complexation modeling of Fe3O4-H+ and Mg(II) sorption onto maghemite and magnetite2012In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 386, no 1, p. 260-267Article in journal (Refereed)
    Abstract [en]

    The surface acid/base properties of magnetite (Fe3O4) particles and the sorption of Mg2+ onto magnetite and maghemite (γ-Fe2O3), have been studied using high precision potentiometric titrations, batch experiments and zeta potential measurements. The acid/base properties of magnetite were found to be very similar to maghemite except for the difference in surface site density, Ns (sites nm-2), 1.50±0.08 for magnetite and 0.99±0.05 for maghemite. The experimental proton exchange of the magnetite surface increased from pH 10 and above, indicating dissolution/transformation reactions of magnetite at alkaline conditions. Thus, magnetite with its Fe(II) content proved to be less stable towards dissolution in comparison with pure Fe(III) oxides also at high pH values.Three different ratios between surface sites and added Mg2+ were used in the sorption experiments viz. 0.5, 1 and 2 Mg2+ site-1. Surface complexation modeling of the Mg2+ sorption onto maghemite and magnetite, was restricted to pH conditions where the interference from Mg(OH)2(s) precipitation could be ruled out. The model calculations showed that Mg2+ sorb onto the magnetite and maghemite surfaces as a mixture of mono- or bidentate surface complexes at 0.5 Mg2+ site-1 and as monodentate complexes at 1 and 2 Mg2+ site-1 conditions. Mg2+ was also found to adsorb more readily at the maghemite surfaces in comparison with magnetite surfaces. For experiments with excess Mg2+ relative to the number of surface sites, the calculations suggested the formation of polynuclear surface complexes on maghemite.

  • 15.
    Kovács, Krisztina
    et al.
    Eötvös Loránd University.
    Kuzmann, E.
    Hungarian Academy of Sciences.
    Homonnay, Z.
    Hungarian Academy of Sciences.
    Vértes, Attila
    Hungarian Academy of Sciences.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Sandström, Åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Mössbauer study of synthetic jarosites2008In: Hyperfine Interactions, ISSN 0304-3843, E-ISSN 1572-9540, Vol. 186, no 1-3, p. 69-73Article in journal (Refereed)
    Abstract [en]

    57Fe Mössbauer spectroscopy and PXRD were used to study artificially prepared jarosites with the compositions of KFe3(SO4)2(OH)6 - x F x x = 0 - 1.6 PXRD measurements revealed single phase jarosite samples. All Mössbauer spectra taken at room temperature exhibit a quadrupole doublet corresponding to mineral jarosite. However, at low temperature where the mineral jarosite has a well resolved sextet, the synthetic jarosite even with x = 0 F -  content shows a relaxation transition. The spectra indicate that with increasing F -  concentration, the paramagnetic-antiferromagnetic transition temperature is decreasing. The results can be used in the analysis of artificial jarosites or those formed during biomineralization processes.

  • 16.
    Lindström, E. Börje
    et al.
    Unit for Applied Cell and Molecular Biology, University of Umeå, Umeå, Sweden.
    Gunneriusson, Lars
    Department for Inorganic Chemistry, University of Umeå, Umeå, Sweden.
    Thermophilic bioleaching of arsenopyrite using Sulfolobus and a semi-continuous laboratory procedure1990In: Journal of Industrial Microbiology & Biotechnology, ISSN 1367-5435, E-ISSN 1476-5535, Vol. 5, no 6, p. 375-382Article in journal (Refereed)
    Abstract [en]

    A laboratory equipment for pumping slurries is described. The pumping is performed semi-continuously by using a plastic syringe, a set of different valves, and a programmable electronic unit. The reproducibility of the pumping is demonstrated. Bioleaching of a gold-containing arsenopyrite slurry was done withSulfolobus at 70°C using the semi-continuous procedure and with a retention time of 100 h for the mineral. Arsenic was completely released at a rate of 109 mg l-1 h-1. The gold recovery is related to the amount of iron and arsenic dissolved and is shown to have a correlation factor of approximately one relative to the release of arsenic.

  • 17.
    Lützenkirchen, J.
    et al.
    Institut für Nukleäre Entsorgung, Forschungszentrum Karlsruhe.
    Boily, J.F.
    Pacific Northwest National Laboratory , Richland, WA.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Lövgren, L.
    Department of Chemistry, Umeå University.
    Sjöberg, S.
    Department of Chemistry, Umeå University.
    Protonation of different goethite surfaces: unified models for NaNO3 and NaCl media2008In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 317, no 1, p. 155-165Article in journal (Refereed)
    Abstract [en]

    Acid–base titration data for two goethites samples in sodium nitrate and sodium chloride media are discussed. The data are modeled based on various surface complexation models in the framework of the multi site complexation (MUSIC) model. Various assumptions with respect to the goethite morphology are considered in determining the site density of the surface functional groups. The results from the various model applications are not statistically significant in terms of goodness of fit. More importantly, various published assumptions with respect to the goethite morphology (i.e., the contributions of different crystal planes and their repercussions on the “overall” site densities of the various surface functional groups) do not significantly affect the final model parameters within simple 1-pK approximations. The simultaneous fit of the chloride and nitrate data results in electrolyte binding constants, which are applicable over a wide range of electrolyte concentrations including mixtures of chloride and nitrate. Model parameters for the goethite sample with 90 m2/g specific surface area are in excellent agreement with parameters that were independently obtained by another group on different goethite titration data sets.

  • 18. Ruth, Katja Viventsova
    et al.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Holmgren, Allan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Changes in soil organic matter composition and quantity with distance to a nickel smelter: a case study on the Kola Peninsula, NW Russia2005In: Geoderma, ISSN 0016-7061, E-ISSN 1872-6259, Vol. 127, no 3-4, p. 216-226Article in journal (Refereed)
    Abstract [en]

    The capacity of soils to absorb contamination depends on a number of factors, such as soil organic matter (SOM) that plays an essential role in adsorption of metal ions, especially in Podzols with their low content of clay minerals. Detailed analysis of SOM can provide information about the potential capacity of a soil to mobilise or immobilise contaminating substances, which in turn can be used to predict potential recovery of the soil ecosystem following heavy metal pollution. The purpose of this study was to learn how an increasing load of heavy metals (Cu and Ni) affects SOM content and structure, and which of the SOM functional groups are responsible for metal retention. The study area is located in the central part of the Kola Peninsula, south of Monchegorsk city and the nickel smelting complex ‘Severonickel’. The amount of total carbon in the soil decreased from 86% to 0.6% as the distance from the smelting complex decreased from 34 to 2 km. Functional groups of the SOM had a larger diversity in less polluted soils than in the soils located closer to the smelting complex. Carboxyl groups had a higher intensity of infra red (IR) bands in soils collected at the distance of 34–27 km than those located closer to the smelter. The most disturbed soil at the site closest to the smelter showed almost no presence of COOH groups. We conducted a laboratory experiment using soils from the least polluted sampling site to assess which SOM functional groups may be responsible for metal retention. Experimental contamination of the soil with the Cu/Ni solution resulted in an overall decrease in the absorbance for all studied functional groups within the measured range, except for COOH. This could be attributed both to changes in the structure of the SOM caused by its reaction with the contaminating substances, and to the leaching of some of the organic compounds from the soil during the experiment. Further studies are needed to better understand which functional groups in the SOM are active in the adsorption processes.

  • 19. Sundkvist, Jan-Eric
    et al.
    Sandström, Åke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Lindström, Börje
    Fluorine toxicity in bioleaching systems2005In: Biohydrometallurgy: 16th International Biodrometallurgy Symposium IBS-2005, held in Cape Town, South Africa, September 25-29, 2005 / [ed] Susan T. L. Harrison; D.E. Rawlings; Jochen Petersen, Amsterdam: Elsevier, 2005, p. 19-28Conference paper (Refereed)
  • 20.
    Widerlund, Anders
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Roos, Per
    Lund University.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ingri, Johan
    Holmström, Henning
    Envipro Miljöteknik AB, Linköping.
    Early diagenesis and isotopic composition of lead in Lake Laisan, northern Sweden2002In: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 189, no 3-4, p. 183-197Article in journal (Refereed)
    Abstract [en]

    Water column (dissolved/suspended phase, sediment traps) and sediment data (pore-water, solid-phase sediment) were combined with stable Pb and 210Pb isotope data to trace the early diagenetic behaviour and geochemical cycling of Pb in Lake Laisan, a lake which has received large quantities of anthropogenic Pb since the early 1940s. Early diagenetic remobilisation of Pb is indicated by a subsurface pore-water Pb maximum (120 μg l-1) in the oxic surface layer of the sediment, where the solid-phase Pb concentration is 3400-4600 μg g-1. The remobilisation of Pb appears to be caused by a pH-controlled desorption of Pb from solid-phase sediment, which is consistent with a model describing surface complexation of Pb(II) on hydrous goethite surfaces. The diffusive Pb flux from the subsurface pore-water maximum towards the sediment surface (36 μg cm-2 year-1) exceeds the depositional Pb flux (8.6 μg cm-2 year-1) by approximately a factor of four, indicating that Pb is highly mobile in the sediment. Stable Pb isotope data and a mass balance calculation suggest that Pb diffusing upwards is, to a large extent, trapped in the surface sediment. Lead that may diffuse into the slightly alkaline lake water appears to be efficiently sorbed to suspended particulate matter, resulting in low dissolved Pb concentrations in the water column (0.040-0.046 μg l-1). Sorption of Pb to suspended particulate matter is consistent with the elevated suspended particulate Pb concentrations in the hypolimnion (3800-4000 μg g-1), and the fact that the stable Pb isotopic compositions of suspended matter and pore-water are similar.

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