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Adsorption of dicarboxylates on nano-sized gibbsite particles: effects of ligand structure on bonding mechanisms

Rosenqvist, J.; Axe, K.; Sjoberg, S. and Persson, Per LU (2003) In Colloids and Surfaces A: Physicochemical and Engineering Aspects 220. p.91-104
Abstract
The adsorption of the dicarboxylates o-phthalate, maleate, fumarate, malonate, and oxalate (representing ligands with the general composition -O2C-C-n-CO2; n = 0, 1, or 2) on gibbsite were studied by means of quantitative batch adsorption experiments and attenuated total reflectance Fourier. transform infrared (ATR-FTIR) spectroscopy. The interpretations of ATR-FTIR spectra were aided by comparison with,IR spectra of solution species and by results from theoretical frequency calculations. The main objectives of the study were to identify the molecular level bonding mechanisms of the dicarboxylates to gibbsite, and to investigate how these were influenced by the composition and structure of the ligands. Carboxylates with n = 2 formed... (More)
The adsorption of the dicarboxylates o-phthalate, maleate, fumarate, malonate, and oxalate (representing ligands with the general composition -O2C-C-n-CO2; n = 0, 1, or 2) on gibbsite were studied by means of quantitative batch adsorption experiments and attenuated total reflectance Fourier. transform infrared (ATR-FTIR) spectroscopy. The interpretations of ATR-FTIR spectra were aided by comparison with,IR spectra of solution species and by results from theoretical frequency calculations. The main objectives of the study were to identify the molecular level bonding mechanisms of the dicarboxylates to gibbsite, and to investigate how these were influenced by the composition and structure of the ligands. Carboxylates with n = 2 formed predominantly outer sphere complexes, whereas the importance of inner sphere complexes progressively increased for n = I and 0. The inner sphere structures were identified as mononuclear chelates with one oxygen from each carboxylate group bonded to Al(111) at the surface. This showed the importance of chelate ring structure for the formation-of inner sphere surface complexes, with stabilities of the complexes increasing in the order seven-membered ring less than six-membered ring less than five-membered ring. For ligands with n = 2 only small variations in surface speciation were observed as a function of steric factors; irrespective. of the. relative positions of the carboxylate groups and bulkiness of the ligands outer sphere bonding is the dominating adsorption model Adsorption experiments were also conducted with gibbsite particles exhibiting differences in shape and surface roughness. These experiments showed that inner sphere complexes were favored on the less well-developed and more irregular gibbsite particles. (C) 2003 Elsevier Science B.V. All. rights reserved. (Less)
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author
publishing date
type
Contribution to journal
publication status
published
subject
in
Colloids and Surfaces A: Physicochemical and Engineering Aspects
volume
220
pages
91 - 104
publisher
Elsevier
external identifiers
  • scopus:0038009347
ISSN
0927-7757
DOI
10.1016/S0927-7757(03)00063-3
language
English
LU publication?
no
id
3b6f2cc0-e6f7-4c0f-bba2-3563f7fe60cb (old id 4332547)
date added to LUP
2014-03-04 09:41:57
date last changed
2018-10-03 11:30:53
@article{3b6f2cc0-e6f7-4c0f-bba2-3563f7fe60cb,
  abstract     = {The adsorption of the dicarboxylates o-phthalate, maleate, fumarate, malonate, and oxalate (representing ligands with the general composition -O2C-C-n-CO2; n = 0, 1, or 2) on gibbsite were studied by means of quantitative batch adsorption experiments and attenuated total reflectance Fourier. transform infrared (ATR-FTIR) spectroscopy. The interpretations of ATR-FTIR spectra were aided by comparison with,IR spectra of solution species and by results from theoretical frequency calculations. The main objectives of the study were to identify the molecular level bonding mechanisms of the dicarboxylates to gibbsite, and to investigate how these were influenced by the composition and structure of the ligands. Carboxylates with n = 2 formed predominantly outer sphere complexes, whereas the importance of inner sphere complexes progressively increased for n = I and 0. The inner sphere structures were identified as mononuclear chelates with one oxygen from each carboxylate group bonded to Al(111) at the surface. This showed the importance of chelate ring structure for the formation-of inner sphere surface complexes, with stabilities of the complexes increasing in the order seven-membered ring less than six-membered ring less than five-membered ring. For ligands with n = 2 only small variations in surface speciation were observed as a function of steric factors; irrespective. of the. relative positions of the carboxylate groups and bulkiness of the ligands outer sphere bonding is the dominating adsorption model Adsorption experiments were also conducted with gibbsite particles exhibiting differences in shape and surface roughness. These experiments showed that inner sphere complexes were favored on the less well-developed and more irregular gibbsite particles. (C) 2003 Elsevier Science B.V. All. rights reserved.},
  author       = {Rosenqvist, J. and Axe, K. and Sjoberg, S. and Persson, Per},
  issn         = {0927-7757},
  language     = {eng},
  pages        = {91--104},
  publisher    = {Elsevier},
  series       = {Colloids and Surfaces A: Physicochemical and Engineering Aspects},
  title        = {Adsorption of dicarboxylates on nano-sized gibbsite particles: effects of ligand structure on bonding mechanisms},
  url          = {http://dx.doi.org/10.1016/S0927-7757(03)00063-3},
  volume       = {220},
  year         = {2003},
}