Change search
ReferencesLink to record
Permanent link

Direct link
Surface Complexation of Mellitic Acid to Goethite: An Attenuated Total Reflection Fourier Transform Infrared Study
Umeå University, Faculty of Science and Technology, Chemistry.
Umeå University, Faculty of Science and Technology, Chemistry.
Umeå University, Faculty of Science and Technology, Chemistry.
2004 (English)In: Langmuir, ISSN 0743-7463, Vol. 20, no 3, 823-8 p.Article in journal (Refereed) Published
Abstract [en]

The nature of the interaction between mellitic acid (benzene hexacarboxylic acid) and the common soil mineral goethite (-FeOOH) has been investigated as a function of pH and ionic strength by use of attenuated total reflection Fourier transform infrared spectroscopy. Molecular orbital calculations of the theoretical vibrational frequencies of the mellitate ion (L6-) and dihydrogen mellitate (H2L4-) have allowed the measured absorption frequencies to be accurately assigned. At pH values above 6, adsorption involves outer-sphere complexation of the deprotonated L6- ion. At lower pH values, there is evidence of a second outer-sphere surface complex involving a partially protonated species, although the extent of protonation of the surface species is significantly less than that found for the solution species at the same pH. While there is no evidence of inner-sphere complexation, increasing the ionic strength to 2.0 M does not displace the adsorbed species but does increase the fraction present on the surface as the fully deprotonated L6-. The small effect of ionic strength suggests that the adsorptive interaction, although outer-sphere in character, is still relatively strong, which indicates that hydrogen bonds may play a significant role. Hydrogen bonding may also help to account for the observed outer-sphere complexation at pH values above the pHiep of goethite.

Place, publisher, year, edition, pages
2004. Vol. 20, no 3, 823-8 p.
URN: urn:nbn:se:umu:diva-14331DOI: doi:10.1021/la035471oOAI: diva2:154002
Available from: 2007-05-28 Created: 2007-05-28 Last updated: 2011-01-12Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Sjöberg, StaffanPersson, Per
By organisation

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 25 hits
ReferencesLink to record
Permanent link

Direct link