| Pyrolysis of biomass waste produces pyrolysis oil (PO), a complex mixture of oxygenated compounds. More than four hundred compounds have been identified in PO. PO can be upgraded to transportation fuel through hydrodeoxygenation (HDO). In this thesis, HDO of pyrolysis oil, and two model compounds of pyrolysis oil, acetic acid, and 4-propyl guaiacol, representing the hemicellulose- and lignin-derived components respectively, was performed in a packed bed microreactor using reduced sulfided NiMo/Al2O3 catalyst. High acid content (up to 25 wt. % acetic acid in some pyrolysis oils) renders pyrolysis oil corrosive, and this acidity needs to be reduced for long term storage. 4-propyl guaiacol represents some of the major lignin-derived compounds present in pyrolysis oil. By studying the hydrodeoxygenation of 4-Propyl guaiacol, we will gain a better understanding of the upgrading mechanism and kinetics of pyrolysis oil. Finally, the hydrodeoxygenation of whole pyrolysis oil was investigated.;In the performance study, temperature was found to exert the most influence on the conversion indicating kinetic effect. Comparable results to literature values were demonstrated by performing hydrodeoxygenation at operating pressures less than 500 psig compared to the 1000 - 3000 psig pressure required for the conventional reactors. Coke formation was less than 1wt. % during four hours of hydrodeoxygenation of pyrolysis oil. Removable oxygen content in the pyrolysis oil was reduced from 27% to 21% by conducting hydrodeoxygenation at 180 °C and 300 psig. High hydrogen consumption indicated the occurrence of hydrogenation in parallel with hydrodeoxygenation. The maximum values of conversion and product yield were reached in a residence time of less than a second because mass and heat transfer resistances are negligible in a microreactor. The comparison of reactor diameters showed that the microreactor with an internal diameter less than 1 mm performed better in terms of space-time-yield.;For the kinetic study, reaction rate expressions for the hydrodeoxygenation of 4-propyl guaiacol were proposed based on reaction mechanisms developed using the Langmuir-Hinshelwood approach. Non-linear regressions were performed to obtain the best fitted rate equations and kinetic constants. The best fitted rate equations were further validated by comparing experimental data obtained from an integral reactor with predicted data obtained using Runge-Kutta method. |
