Document Detail


Interactions between GaO(4)Al(12)(OH)(24)(H(2)O)(12)(7+) and cellulosic materials.
MedLine Citation:
PMID:  22386204     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
The adsorption qualities of GaO(4)Al(12)(OH)(24)(H(2)O)(12)(7+), a polycation with ε-Keggin structure, and its stability in contact with anionic cellulosic materials, was investigated under different concentration and ionic strength conditions. The cellulosic materials employed were two different fully bleached fibre materials, carboxyl methyl cellulose (CMC), and a spin-coated cellulose model surface. As analytical techniques, pH-measurements, potentiometric titrations, ICP-OES, QCM-D, equilibrium calculations and Extended X-ray Absorption Fine Structure (EXAFS) were used. The adsorption is substantial and the addition of GaO(4)Al(12)(OH)(24)(H(2)O)(12)(7+) to a fibre suspension results in a rapid decrease in pH, followed by a small and slow increase in pH. This behaviour can be explained as due to a rapid and strong (log β>2) equilibrium adsorption of intact GaO(4)Al(12)(OH)(24)(H(2)O)(12)(7+) ions, followed by a slow, and minor, 3-8%, decomposition into different monomers. Alternative layer by layer adsorption of this ion, and CMC, on a spin-coated cellulose model surface constitutes further evidence for the strong interactions between the anionic cellulose materials and GaO(4)Al(12)(OH)(24)(H(2)O)(12)(7+). It is shown that the adsorption observed could not be described as due to an unspecific Donnan adsorption behaviour, neither of GaO(4)Al(12)(OH)(24)(H(2)O)(12)(7+) nor Ga and Al monomers, and specific surface complex formation is therefore discussed and applied. The (≡COO)(7)GaO(4)Al(12)(OH)(24)(H(2)O)(12) species found to explain the pH- and metal adsorption data should be considered strictly as a stoichiometric entity.
Authors:
Ola Sundman; Per Persson; Dipanjan Banerjee; Lars-Olof Ohman
Related Documents :
22043964 - Analysis of incurred crystal violet in atlantic salmon (salmo salar l.): comparison bet...
23873064 - Influence of supramolecular structures in crystals on parallel stacking interactions be...
4348784 - Octahedral crystals in phycomyces. ii.
22054434 - Carbon dioxide evolution of refrigerated meat.
17327674 - On the routine use of soft x-rays in macromolecular crystallography. part iv. efficient...
24343584 - Synthesis and characterisation of new mo(oh)2 (m = zr, hf) oxyhydroxides and related li...
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2012-2-15
Journal Detail:
Title:  Journal of colloid and interface science     Volume:  -     ISSN:  1095-7103     ISO Abbreviation:  -     Publication Date:  2012 Feb 
Date Detail:
Created Date:  2012-3-5     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0043125     Medline TA:  J Colloid Interface Sci     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Copyright Information:
Copyright © 2012 Elsevier Inc. All rights reserved.
Affiliation:
Department of Chemistry, Umeå University, S-901 87 Umeå, Sweden; Department of Forest Products Technology, Aalto University School of Chemical Sciences, P.O. Box 16300, FI-02015 Aalto, Finland.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Adsorption of nanoparticles at the solid-liquid interface.
Next Document:  Electrochemical characterization of Self-assembled Monolayers (SAMs) of silanes on indium tin oxide ...