(532j) Design of Bi-Functional Zeolite-Based Catalysts for Bio-Oil Upgrading into Fuels

Self-pillared pentasil (SPP) is a hierarchical MFI zeolite synthesized using organic structure directing agents to template the zeolite for obtaining self-pillared nanosheets of the MFI structure. Self-pillared MFI supports with transition metal catalysts provide good candidates for the hydrodeoxygenation reaction. However, transition metals, such as nickel, can cause coke formation at high conversions, which is why they are often co-loaded with noble metals, such as platinum. The bi-metallic nature secures the low deactivation rates, while the MFI support provides good diffusion rates in addition to possible enhancements in metal dispersion and synergy. This work aims at studying the influence of bi-metallic loading along with the textural properties and morphology of MFI supports on the hydrodeoxygenation of oleic acid, by testing platinum-nickel bi-metallic catalysts with different platinum content and comparing them with mono-metallic nickel catalysts prepared using conventional and self-pillared MFI supports. For this project, the synthesis of a viable self-pillared MFI zeolite was successfully delivered following an optimization protocol. Moreover, multiple Ni and Ni/Pt-loaded catalysts were synthesized using the ion-exchange and incipient wetness impregnation techniques. The microstructure, porosity, and surface acidity of the zeolite-based catalysts were studied by employing X-ray diffraction, High Resolution Transmission Electron Microscopy (HR-TEM), N₂ adsorption at 77K and NH₃-temperature programmed desorption. From TEM imaging, it was observed that the metal dispersion for impregnated self-pillared samples was much better than that achieved by their conventional counterparts, where the metal particles for SPP samples were mostly less than 10 nm. On the other hand, the metal particles observed on the external surfaces of impregnated conventional MFI samples were mostly too big to fit into the pores of the support (> 100 nm) causing a drop in porosity due to blocking of pore entrances. Additionally, the bimetallic samples achieved enhanced reducibility and higher acidity as compared to monometallic samples.