Cumulative exergy analysis of lignocellulosic biomass to bio-jet fuel through aqueous-phase conversion with different lignin conversion pathways

Lignocellulosic biomass conversion to bio-jet fuel is beneficial for reducing the depletion of fossil fuel. This study presented and compared the two different pathways of lignin in corn stalk to bio-jet fuel via aqueous-phase conversion based on the process simulation approach and life cycle cumulative exergy analysis. The results show that the pathway of lignin one-step conversion (LJA) can obtain a higher bio-jet fuel yield and cumulative exergy efficiency than lignin two-step conversion (LJC). Moreover, biomass conversion to bio-jet fuel with selfsupplied hydrogen is beneficial to the conversion of low-quality biomass into high-quality bio-jet fuel and the decrease in fossil fuel consumption. Under the optimal parameters, corn stalk aqueous-phase conversion to biojet fuel with external-supplied hydrogen can achieve the largest bio-jet fuel yield (142.7 kg/t-bio) and cumulative exergy efficiency of system (29.3%). The sensitivity analyses show that the hydrolysis efficiency of lignin has the most influence on the cumulative exergy efficiency of bio-jet fuel, while the furfural yield from hemicellulose has the lowest impact. When the consumption of chemicals and steam is considered, it is significant to reduce the stripping steam to furfural ratio for the cumulative exergy efficiency and reduce the consumption of methanol and sulfuric acid for the renewability.

Automated summary

This study presents and compares two different pathways of lignin conversion to bio-jet fuel from corn stalks. The one-step conversion pathway yields higher bio-jet fuel and cumulative exergy efficiency compared to the two-step conversion pathway. Biomass conversion to bio-jet fuel with self-supplied hydrogen aids in converting low-quality biomass into high-quality bio-jet fuel and reducing fossil fuel consumption. Sensitivity analysis shows that the hydrolysis efficiency of lignin has the greatest impact on cumulative exergy efficiency, while the furfural yield from hemicellulose has the lowest impact.