Substances Adsorbed or Entrapped at the Gelation Step

2 Molecular Substances Adsorbed or Entrapped at the Gelation Step 

The preparations and performance of molecular catalysts successfully heterogenized by physical entrapment for a wide range of reactions are reviewed in detail in [86,93]. Two synthetic protocols were used, depending on the chemical properties of entrapped molecules addition of dopant solution to prehydrolyzed Si(OR)4 at pH close to 7, or together with ammonium hydroxide to tetraalkoxysilane precondensed in acidic solution. Both, followed by gelation. 

Sing and J. Weitkamp), Wiley-VCH Verlag GmbH, Weinheim, Vol. 7, p. 1677. 

(2007) Kirk-Othmer Encyclopedia of Chemical Technology, 5th edn, John Wiley Sons, Inc., New York, Vol. 23, pp. 53-84. 

Livage, J., Henry, M. and Sanchez, C. (1988) Prog. Solid State Chem., 18, 259. 

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