Influence of the Preparation Method and Metal Precursor Compound on the Bifunctional Ni/HZSM-5 Catalysts

Abstract

The influence of the preparation method and the nature of the precursor compound on the hydroisomerization activity of nickel catalysts was studied. Two preparation methods, mechanical mixing, and incipient wetness impregnation, with different precursor compounds were used to manufacture catalysts containing 2, 5, and 10 wt % of nickel. Temperature-programmed desorption of ammonia (TPDA), temperature-programmed reduction, scanning electron microscopy, X-ray diffraction line broadening, and atomic absorption spectroscopy techniques were used to characterize the catalysts. Catalytic behavior was tested by hydroisomerization of n-decane reactions. TPDA measurements revealed that acid strength distribution of the catalysts prepared by impregnation differs from that of the bare zeolite whereas the catalysts prepared by mechanical mixing showed similar acid strength distribution than zeolites. Nickel reducibility depends on the preparation method as well as the nickel precursor compound. Incipient wetness impre...