Abstract: Nickel supported catalysts were prepared by impregnating nickel on SAPO-11, USY and ZSP-3 molecular sieves. BET, XRD, NH3-TPR and pyridine adsorption-desorption FT-IR were used to characterize the prepared catalysts. The hydroisomerization and hydroaromatization performance of these catalysts were evaluated with a micro-reactor using n-octane as model compound. Test results indicated that among the three catalysts, Ni/SAPO-11 showed the highest isomerization selectivity and good aromatization selectivity, but its conversion was the lowest; Ni/ZSP-3 showed the highest conversion and aromatization selectivity, yet its isomerization selectivity was the lowest; Ni/USY showed moderate isomerization selectivity and conversion, however, its aromatization selectivity was poor. Using ZSP-3 molecular sieve modified by rare earth cations as support, the surface acid center distributions of catalyst were altered, resulting in an enhancement of catalyst selectivity to isomerization and aromatization.

Key words: n-octane, hydroisomerization, hydroaromatization, molecular sieve, acidity