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Effect of γ-irradiation on the catalytic activity and selectivity of γ-alumina II. Conversion of isopropanol

  • G. A. El-Shobaky
  • N. H. Amin
  • G. A. Fagal
Article

Abstract

The catalytic conversion of isopropanol was conducted over a poorly crystalline γ-alumina irradiated with different doses of γ-rays (25–150 Mrad). The catalytic reaction was carried out at 180–400°C in a flow technique under atmospheric pressure. The results showed that the dose of 25 Mrad resulted in a decrease of about 50% of the dehydration activity which suffered a further slight decrease upon irradiation at a dose of 50 Mrad. Increasing the dose in the range of 50–150 Mrad effected an increase in the dehydration activity reaching a maximum limit at 100 Mrad, then decreased abruptly by a dose of 150 Mrad. γ-irradiation led also to creation of some active sites contributing in dehydrogenation of isopropanol to producing acetone. These results were discussed in terms of removal of Brönsted acidity (25–50 Mrad), responsible for the dehydration reaction and to transformation of Lewis to Brönsted acidity (100 Mrad) by the action of liberated water from the dehydration reaction. The drop in dehydration activity due to irradiation at 150 Mrad might result from an efficient removal of the Brönsted acid sites created. The induced dehydrogenation activity of irradiated aluminas was attributed to creation of some electron-donor centers.

Keywords

Acetone Acidity Catalytic Activity Dehydration Isopropanol 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Akadémiai Kiadó 1994

Authors and Affiliations

  • G. A. El-Shobaky
    • 1
  • N. H. Amin
    • 2
  • G. A. Fagal
    • 1
  1. 1.Department of Physical ChemistryNational Research CentreCairo(Egypt)
  2. 2.Chemistry Department, Faculty of EducationAin-Shams UniversityCairo(Egypt)

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