(277c) Ex Situ Hydrodeoxygenation in Biomass Pyrolysis Using Molybdenum Oxide and Low Pressure Hydrogen

A major challenge with the utilization of bio-oil produced from the fast pyrolysis of biomass is its high oxygen content.  Therefore, significant efforts have been directed towards the efficient removal of oxygen while minimizing the loss of carbon products. Discussed will be the ex situ hydrodeoxygenation of biomass pyrolysis vapors, which was performed in a tandem micropyrolyzer system using low pressure hydrogen, a molybdenum oxide catalyst, and cellulose, lignin, and corn stover as feedstocks. The MoO₃ catalyst was found to be very effective at producing hydrocarbons from the highly oxygenated pyrolysis vapors. An initial induction period was needed to reduce the catalyst to a more active form in order to fully deoxygenate the pyrolysis vapors from the first feed injection. The hydrocarbon products consisted of primarily linear alkanes (C₁ to C₆) and monocyclic aromatics with the total hydrocarbon yield being up to a remarkably efficient ~75-90 C% for the three feedstocks.