Biomass hydrodeoxygenation

Oxygen can be present in naphthenic acids, phenols and furan (analogue structures to thiophene and pyrrole) and higher derivatives. Oxygenated compounds give rise to corrosion and product deterioration. Hydrodeoxygenation is particularly important in the upgrading of biomass. 

Elliott, D. C. and E. G. Baker. "Upgrading Biomass Liquefaction Products Through Hydrodeoxygenation," in Biotechnology and Bioengineering. Symposium No. 14. John Wiley and Sons, New York, 1984 p 159. 

D.C. Elliot E.G. Baker, "Upgrading Biomass Liquefaction Products through Hydrodeoxygenation", Biotechnology Bioengineering Symp. H, 159-174 (1984). 

Conversion of biomass at a temperature of 300 350 °C and a pressure of 120-180 bar within the so-called HydroThermal Upgrading (HTU) process yields a mixture of hydrocarbons, carbon dioxide, water and dissolved organics, which can be further processed in a catalytic HydroDeOxygenation (HDO) step to yield diesel with characteristics similar to fossil diesel. A major advantage is that wet biomass feedstocks can be employed without drying in contrast, water at hydrothermal conditions acts as a solvent and reactant at the same time, leading to a product with less oxygen compared to biocrude prepared by pyrolysis. 

In recent years, the production of simple hydrocarbrnis from biomass has attracted strong interest in the renewables community, due to the fact that the products are considered drop-in substitutes for petroleum-derived alkanes, with evident applications to fuels and chemical production. HMF has received much attention in this regard as a platform for extended carbon chain products, the hydrodeoxygenation (HDO) of which gives products which are essentially diesel or aviation fuels, depending on their hydrocarbon distribution. Aldol-type condensation reactions can take place in aqueous solution between HMF (or its derivatives) and biogenic ketones... 

The hydrodeoxygenation plays a minor role in the case of the conventional feeds, whereas for the feeds derived from coal, oil shale, and, particularly from the biomass, its role can be rather crucial. This process also occurs during the hydroprocessing of petroleum fractions along with hydrodesulfurization, hydrodenitrogenation. 

HDO [HydroDeOxygenation] A general name for processes that remove oxygenates from various biomass-derived products before they can be used as motor fuels. A variety of processes and catalysts will accomplish this. 

Centeno A, David O, Vanbellinghen C, Maggi R, Delmon B. 1997. Behaviour of catalysts supported on carbon in hydrodeoxygenation reactions. In Bridgwater AV, Boocock DGB (editors). Developments in Thermochemical Biomass Conversion, Vol. 1. London Blackie Academic Professional. 

De, S., Saha, B., Luque, R., 2015. Hydrodeoxygenation processes advances on catalytic transformations of biomass-derived platform chemical into hydrocarbon fuels. Bioresource Technology 178, 108-118. 

Nakagawa, Y., Liu, S.B., Tamura, M., Tomishige, K., 2015. Catalytic total hydrodeoxygenation of biomass-derived polyfimctionalized substrates to alkanes. ChemSusChem 8 (7), 1114-1132. 

Mayeur, V., Preau, A., Oct. 3, 2013. Process for Hydrodeoxygenation and Process for Upgrading of Pyrolysis Oil Resulting from Biomass, Which Are Capable of Operating Continuously. U.S. patent application 2013/0255138 Al. 

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