SILPAKORN UNIVERSITY JOURNAL OF SOCIAL SCIENCES, HUMANITIES, AND ARTS, Vol. 3 (Number 1-2) 2003

Basicity of MgO by Temperature Programmed Desorption of Phenol

Supanee Chayabutra, B.V.O’ Grady, F.P. Larkins








Abstract


Temperature programmed desorption (TPD) of phenol on MgO
was studied using several detection techniques including thermal
conductivity, infrared spectroscopy, differential thermo-gravimetric
analysis and differential scanning calorimetry to explore the surface
sites of the catalysts. It was found that phenol is an effective probe
molecule for both qualitative and quantitative in the determination of
the surface sites on MgO. The different surface sites of different
basic strength can be distinguished via the desorption profiles
obtained as phenol is desorbed with the increasing temperatures.
Results from all techniques are in agreement. Three chemisorption
peaks are observed. They could be attributed to the flat surface
sites exposure {100} and surface sites of low coordination number,
edges and corners. The amount of coverage on each site was also
determined.

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