Molecular Chemical Aspects of Silica Gel Formation

  • Peter W. J. G. Wijnen
  • Theo P. M. Beelen
  • Rutger A. van Santen


This chapter describes some molecular chemical aspects of the formation of silica gels from aqueous silicate solutions. Experiments involved silicon-29 nuclear magnetic resonance spectroscopy and small-angle scattering of X-rays. Cations are shown to significantly affect the dissolution and oligomerization processes responsible for the formation of silica gels. Aging of aqueous silica gels is described in terms of the changes in fractal dimensionality of the silica structure. Preliminary SAXS experiments on gel transformations occurring in zeolite A synthesis mixtures indicate large-scale changes in gel morphology before crystalline zeolite formation occurs.


Silicate Solution Microporous Material Fractal Dimensionality Silicate Species Zeolite Synthesis 
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Copyright information

© Springer Science+Business Media New York 1992

Authors and Affiliations

  • Peter W. J. G. Wijnen
    • 1
  • Theo P. M. Beelen
    • 1
  • Rutger A. van Santen
    • 1
  1. 1.Schuit Institute of CatalysisEindhoven University of TechnologyThe Netherlands

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