Catalysis Letters

, Volume 58, Issue 2, pp 81–87

On the acidity of liquid and solid acid catalysts. Part 2. A thermodynamic and kinetic study for acid-catalysed nitrations

Authors

  • Nunziata Clara Marziano
    • INFM and Chemistry DepartmentUniversity of Venice
  • Claudio Tortato
    • INFM and Chemistry DepartmentUniversity of Venice
  • Lucio Ronchin
    • INFM and Chemistry DepartmentUniversity of Venice
  • Federica Martini
    • INFM and Chemistry DepartmentUniversity of Venice
  • Claudia Bianchi
    • Department of Physical Chemistry and ElectrochemistryUniversity of Milan
Article

DOI: 10.1023/A:1019073732760

Cite this article as:
Marziano, N.C., Tortato, C., Ronchin, L. et al. Catalysis Letters (1999) 58: 81. doi:10.1023/A:1019073732760

Abstract

Solid acids prepared by adding sulfuric acid on silica gel have been used as catalysts in the nitration of nitrobenzenes and their properties have been tested by kinetic studies at 25°C. Nitration rates in concentrated aqueous solutions of sulfuric acid were also analysed and the catalytic efficiencies of sulfuric acid in liquid and solid phase were compared by using kinetic data of analogous compounds. The results show that the solid acid samples exhibit nitrating properties very similar to those observed in concentrated aqueous solutions of sulfuric acid (range of 90 wt%). The relationship between nitration rates and effective concentration of electrophilic species [NO 2 + ], determined by studying the protonation–dehydration equilibrium of nitric acid in strong acids (HNO3 + H+ ⇌ H2O + NO 2 + ), was tested to better understand the acidity properties of medium.

nitration sulfuric acid solid acid catalysts

Copyright information

© Kluwer Academic Publishers 1999