Hydrocarbon production by continuous hydrodeoxygenation of liquid phase pyrolysis oil with biogenous hydrogen rich synthesis gas

Abstract

This paper presents a beneficial combination of biomass gasification and pyrolysis oil hydrodeoxygenation for advanced biofuel production. Hydrogen for hydrodeoxygenation (HDO) of liquid phase pyrolysis oil (LPP oil) was generated by gasification of softwood. The process merges dual fluidized bed (DFB) steam gasification, which produces a hydrogen rich product gas and the HDO of LPP oil. Synthesis gas was used directly without further cleaning and upgrading, by making use of the water gas-shift (WGS) reaction. The water needed for the water gas-shift reaction was provided by LPP oil. HDO was successfully performed in a lab scale over 36 h time on stream (TOS). Competing reactions like the Boudouard reaction and Sabatier reaction were not observed. Product quality was close to Diesel fuel specification according to EN 590, with a carbon content of 85.4 w% and a residual water content of 0.28 w%. The water-gas shift reaction was confirmed by CO/CO₂-balance, high water consumption and 28% less hydrogen consumption during HDO.