Suja, H; Deepa, C S; Sreeja Rani, K; Sugunan, S(Indian Journal of Chemistry, August , 2003)
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Abstract:
The present work attempts a systematic examination of the effect of sulphate content on the physico-chemical properties
and catalytic activity of sulphated zirconia and iron promoted sulphated zirconia systems. Sulphate content is estimated by
EDX analysis. The amount of sulphate incorporated has been found to influence the surface area, crystal structure and the
acid strength distribution. Ammonia TPD and adsorption studies using perylene have enabled the determination of surface
acidic properties. The results are supported by the thermodesorption studies using pyridine and 2,6-dimethylpyridine. The
catalytic activity towards benzoylation reaction has been correlated with the surface acidity of the systems.
Suja, Haridas; Dr.Sugunan, S(Cochin University of Science & Technology, January , 2002)
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Abstract:
The present project was a systematic investigation of the
physico-chemical properties and catalytic activity of some transition metal promoted
sulphated zirconia systems. The characterisation and catalytic activity results were
compared with that of pure Zr02 and simple sulphated zirconia systems. Sulphated
zirconia samples were prepared by a controlled impregnation technique. In the case of
metal incorporated systems, a single step impregnation was carried out using required
amounts of sulphuric acid and metal salt solutions. As a preliminary step, optimisation of
calcination temperature and sulphate content was achieved. For further studies, the
optimised sulphate loading of 10 ml per gram of hydrous zirconium oxide and a
calcination temperature of 700°C was employed. Metal incorporation had a positive
influence on the physico-chemical properties. Vapour phase cumene conversion served as
a test reaction for acidity. Some industrially important reactions like Friedel-Crafts
reaction, phenol hydroxylation, nitration, etc. were selected to test the catalytic activity of
the prepared systems.
Description:
Department of Applied Chemistry,
Cochin University of Science and Technology