A critical review on the production and upgradation of sustainable biocrude from hydrothermal liquefaction of Canadian-grown agricultural biomass

Abstract

Oxygenated biocrude produced from hydrothermal liquefaction is of great interest as it originated from renewable feedstocks. However, they cannot be processed immediately in internal combustion engines due to high oxygen, high acidity, viscosity, and instability. Thus, there is a need for upgradation before its direct consumption. This review demonstrated the advancement in hydrothermal liquefaction of agricultural biomass to produce biocrude and catalytic hydrodeoxygenation for obtaining upgraded transportation fuels. Critical research and development on the hydrothermal liquefaction process have been reviewed for over a decade with an increasing magnitude over the last five years. This study summarized the global agricultural feedstocks and focused on Canadian agricultural biomass based on its location and availability. Further, different upgradation technologies were discussed with the main emphasis on hydrodeoxygenation, upgradation catalysts, and affecting parameters to produce deoxygenated renewable fuels. Co-processing, blending with conventional fuels, techno-economic feasibility, and life cycle studies were also elaborated with future perspectives.