Document Type : Research Article
Department of Chemistry, Gielan University, Rasht, P.O. Box 1914 Gielan, I.R. IRAN
Hydrogenation reaction with n-heptane on Pt/Al2O3 catalyst was investigated under the steady state condition in a fixed bed reactor. The catalyst was prepared under a variety of conditions, but the one chosen was non-acidic that is not considered a hydrocracking catalyst. The main objective was to vary the selectivity of n-heptane as a function of reaction variables especially the partial pressure of hydrogen, because in addition to hydrogenolysis, other reactions like isomerization and cyclization also take place. Our studies on selectivity of n-heptane on platinium catalyst shows that in general cracking reactions preferably yield propane and n-butane, and at high pressures methane is also produce as a result of further cracking reactions. Products formed at low pressures (2-10 atm) are: 3-methyl-hexane and 2,3-dimethyl pentane. Those produced with lower yields at higher pressure (20-40 atm) were predominantly 2-methyl hexane and 3-methyl hexane. Dominant cyclic products were 1 tr 2-dimethylcyclopentane, toluent, methylcyclohexane, and ethyl cyclopentane. Upon increasing the hydrogen partial pressure, 1 tr 2-dimethyl cyclopentane increases strongly and those of six membered rings decrease.