EFFECTS OF TEMPLATE AND ADDITIVES ON HYDROISOMERIZATION PERFORMANCE OF Pt/MOR CATALYST

Abstract

Abstract: Hierarchical pore MOR zeolites were synthesized by using sodium dodecyl benzene sulfonate(SDBS), composite polyethylene glycol 20000(PEG20000) and cetyltrimethylammonium bromide(CTAB) as templates, respectively. Pt/MOR catalysts were prepared by loading Pt on MOR zeolites and the second metal components Ni and Cr were respectively introduced into the obtained catalyst by sequential impregnation method. The samples were characterized by XRD, BET, CO pulse chemical adsorption, H2-TPR, NH3-TPD and Py-IR. The results showed that the mesoporous are effectively introduced by the addition of composite templates, the mesoporous surface area and volume of the MOR prepared increase from 36.4% and 52.9% to 54.2% and 76.5%, respectively, and its average pore diameter increases from 2.1 nm to 3.9nm. The introduction of Ni or Cr significantly increases the total acidity and Lewis acid of the catalyst, and remarkably improves the dispersity of the Pt species, and the effect of Cr is better than that of Ni. Over the Pt/MOR catalyst with 1% Cr, the n-octane conversion reaches to 59.3% with the isomerization selectivity of 94.9%.

Key words: Pt/MOR catalyst, template, metal additive, isomerization, n-octane

References

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