Hydrocracking reaction of n-pentane was studied over HZSM-5, Metal-supported HZSM-5 and [Ni]HZSM-5 catalysts.
HZSM-5 and [Ni]HZSM-5 zeolites with various Si/Metal ratios were synthesized in reflux (90℃) and autoclave (175℃) systems and were characterized by SEM, XRD, XRF, BET and TPD methods.
In HZSM-5 catalysis, the density of acid sites decreased as the ratio of Si/$Al_2$ increased, which reduced reactivity. In the case of [Ni]HZSM-5 catalyst, part of Ni adsorbed to surface not being exchanged in lattice. And this catalyst showed lower activity than HZSM-5 one. Ni/HZSM-5 catalyst favored hydrogenolysis and Ni-Mo/HZSM-5 preferred isomerization.
The reaction network of n-pentane hydrocracking on Ni-Mo/HZSM-5(70) catalyst was proposed using the initial selectivity of products. The reaction networks indicated that the isomerization reaction was main reaction.