Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Adsorption and surface complex modeling of silicates on maghemite in aqueous suspensions
Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
2010 (English)In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 342, no 2, p. 493-498Article in journal (Refereed) Published
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.

Place, publisher, year, edition, pages
2010. Vol. 342, no 2, p. 493-498
Keywords [en]
Natural sciences - Chemistry
Keywords [sv]
Naturvetenskap - Kemi
National Category
Physical Chemistry
Research subject
Chemistry of Interfaces
Identifiers
URN: urn:nbn:se:ltu:diva-14062DOI: 10.1016/j.jcis.2009.10.080ISI: 000274117400036PubMedID: 20006343Scopus ID: 2-s2.0-72649084654Local ID: d6084f90-caaf-11de-b769-000ea68e967bOAI: oai:DiVA.org:ltu-14062DiVA, id: diva2:987016
Note
Validerad; 2010; 20091106 (ysko)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textPubMedScopus

Authority records BETA

Jolsterå, RickardGunneriusson, LarsForsling, Willis

Search in DiVA

By author/editor
Jolsterå, RickardGunneriusson, LarsForsling, Willis
By organisation
Sustainable Process Engineering
In the same journal
Journal of Colloid and Interface Science
Physical Chemistry

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 221 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf