Thermochemical processing of woody biomass: A review focused on energy-driven applications and catalytic upgrading

The use of fossil fuels as an energy source and platform of fuel additives can be decreased through the use of woody biomass as a raw material in different conversion processes. In this way, this paper provides an overview of energy-driven applications and insights into the catalytic upgrading of woody biomass. For this purpose, aspects related to technologies, yields, and chemical compounds production were considered. Sustainability concepts are described to improve the evaluation of woody biomass conversion either in a stand-alone process or biorefinery. Besides, this paper provides a case of study to better understand the existing differences between the thermochemical alternatives to convert woody biomass from a techno-economic perspective. This review allows for identifying the use of combustion and gasification processes as the most common alternatives to produce energy. Meanwhile, the wood pellet combustion is the most used for power generation on the residential level. Furthermore, the implementation of heterogeneous catalysis to upgrade syngas and bio-oil into alkanes and alkenes is an increasing trend. On the other hand, the sustainability assessment for the thermochemical upgrading of biomass is still under research. Regarding the case of study, the gasification process presents better techno-economic performance than combustion and pyrolysis since biochar can represent an additional source of income. Nevertheless, this technology must be improved to reach large-scale biomass upgrading. Therefore, this paper offers the readers a vision of the woody biomass conversion through thermochemical processes and catalytic upgrading, considering residential and industrial applications, as well as sustainability aspects.