Abstract
About 90% of the present-day petrochemical industry heavily depends on crude oil
and natural gas. Globally 10% of the crude oil attributes to the production of petrochemicals products, while 50% accounts for transportation fuel, 20% responsible for heating and the remaining 20% for other uses. However, the burning of these limited fossil fuels has been reported as the main source of atmospheric pollution by releasing greenhouse gases.
There is a growing trend to replace these limited fossil fuels with a renewable energy source such as biomass, which is sustainable, does not release carbon dioxide and it is economically beneficial. Herein, we demonstrate how aldol condensation is an important pathway for extending carbon chain of platform molecules such as furfural and levulinic acid to (E)-6-(furan-2-yl)-4-oxohex-5-enoic acid. The structure, functional groups, and purity of the aldol adduct was characterized via Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared spectroscopy (FT-IR) and elemental analysis respectively.
Metal oxide (NiO, Fe2O3, Co3O4, Mn3O4, SiO2, MgO and CaO) were synthesized by sol-gel method. Deposition-precipitation method was used to deposit Pd nanoparticles (NPs) on the different metal oxides. Characterization techniques that include powder X-ray diffraction (p-XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), Brunauer-Emmet-Teller (BET) technique, inductively coupled plasma optical emission spectrometer (ICP-OES), and thermal gravimetric analysis (TGA) were performed to validate the synthesized material. The results showed that Pd NPs ranged from 3 to 11 nm and were dispersed on the metal oxide (MO) supports. The highest BET surface area resulted from Pd-KIT-6 (120.3 m2/g) and the lowest from Pd/NiO (10.4 m2/g).
The prepared Pd-MO catalysts were applied for upgrading aldol adduct into straight chain molecules (biofuel) via hydrodeoxygenation in order to mimic fossil fuel properties by having less oxygen content. Best optimum conditions of the Pd-MO catalyst involve 150 °C, 10 bar hydrogen pressure for 18 hrs. All the Pd-MO catalysts showed selectivity for four different products and furthermore converted 100% of the
vi
substrate except for Pd-NiO (98%). However, the best performing catalyst is Pd-NiO which provided the highest percent for the desired product (decane) and was recycled up to four times without any loss of catalyst activity. This project is part of a bigger MSc project where coursework was done for 1 year and another year for labwork.