Dehydrogenation and Hydrogenation of Hydrocarbons over Platinum-Alumina Catalysts
| Main Authors: | V. KRISHNASAMY, P. MATHUR |
|---|---|
| Format: | Article Journal |
| Bahasa: | eng |
| Terbitan: |
, 1981
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/6358297 |
Daftar Isi:
- A. C. College of Technology, Madras-600 025 Manuscript received 5 July 1980, revised 24 December 1980, accepted 10 March 1981 Cyclohexane and cyclohexene are dehydrogenated over platinum-alumina catalysts containing varying amounts of platinum and platinum-alumina doped with fluoride and caesium ions in the temperature range 250 to 350o, while benzene, toluene, o-xylene and p-cymene are hydrogenated over platinum-alumina D in the temperature range 80 to 250°. The rate of dehydrogenation increases with increasing contact time, registers a maximum around 0.9 hr and then begins to fall. Increase of temperature increases the conversion of cyclohexane over catalysts D and I while it decreases the conversion over catalyst G. Initial addition of platinum upto 0.9% has a beneficial effect on the reactions of cyclohexane and cyclohexene. Subsequent additions bring down the conversions of both. Even though the activity of the catalyst varies with platinum content, its ability to catalyse the conversion of cyclohexene is always more than that of cyclohexane irrespective of platinum concentration. Addition of caesium increases the performance of platinum-alumina whereas addition of hydrogenfluoride decreases it. Cyclohexane formation from cyclohexene by disproportionation increases in the presence of hydrofluoric acid and decreases in the presence of caesium. Hydrogenation increases in each case with temperature, exhibits a maximum and then falls down. The rate of hydrogenation decreases with substitution of alkyl groups.