Original Synthesis and Catalytic Chemistry of Bimetallic Nanoparticle Systems Supported on Nigerian Zeolitic Materials for Hydroprocessing of Non-Edible Plant Oils to Biofuels

Hydroprocessing of non-edible plant oils over bimetallic catalysts offers a route to second-generation biofuels without competing with food supply chains, and the use of locally synthesised zeolitic support materials could significantly reduce catalyst production costs for Nigerian bio-refinery applications. This dissertation presents original synthesis, structural characterisation, and catalytic performance studies of nickel-molybdenum and cobalt-molybdenum bimetallic nanoparticle systems supported on zeolitic materials synthesised from Nigerian kaolin deposits sourced from Kankara, Katsina State. Zeolite synthesis followed hydrothermal crystallisation protocols adapted for the chemical composition of Kankara kaolin, producing ZSM-5 and Y-type zeolite supports confirmed by X-ray diffraction, BET analysis, and 29Si and 27Al solid-state NMR. Bimetallic nanoparticles were deposited by co-impregnation and characterised by energy-dispersive X-ray spectroscopy, high-angle annular dark-field scanning transmission electron microscopy, and temperature-programmed reduction and sulphidation. Hydroprocessing experiments on Jatropha curcas and Calophyllum inophyllum seed oils were conducted in a fixed-bed continuous flow reactor at 350 to 400 degrees Celsius and 40 to 80 bar hydrogen pressure. Product analysis by GC-MS and simulated distillation characterised alkane selectivity and oxygen removal efficiency. The Ni-Mo/ZSM-5 catalyst system achieved 95.8 percent deoxygenation and produced a hydrocarbon product with 84 percent straight-chain alkane content in the diesel boiling range. Catalyst stability over 200 hours on stream was demonstrated. The dissertation establishes an original research basis for integrated Nigerian kaolin-to-catalyst-to-biofuel technology chains. Keywords: bimetallic catalysts, kaolin zeolite, hydroprocessing, biofuels, non-edible oils