Process intensification through furfural purification and reactive distillation in the furan based pathway to sustainable aviation fuel

In recent years, the aviation industry has intensified its efforts to reduce CO₂ emissions, and one of the most promising routes to produce sustainable aviation fuel is the furan route, in which the furfural purification and aldol condensation stages are crucial for the process efficiency. In this work, different process alternatives for both stages were studied, including azeotropic distillation and liquid-liquid extraction processes for the furfural purification stage, while reactive distillation alternatives are explored for the aldol condensation stage. The design considers the evaluation of sustainability indicators such as Total Annual Cost (TAC), Eco-Indicator 99, CO₂ emissions, and individual risk. The results indicate that azeotropic distillation is the most efficient and cost-effective alternative, with a TAC 50% lower and 3% less CO₂ emissions than the LLE options. Additionally, methanol recovery, which is a byproduct of the purification stage, generates revenue that covers nearly 100% of operational costs, significantly improving economic sustainability. Finally, in the aldol condensation stage, conventional reaction–separation processes were compared with intensified configurations such as reactive distillation and thermally coupled reactive distillation. The latter showed the best performance, reducing utility costs by 60%, emissions by 66%, and individual risk by 40%, despite an 18% higher investment cost.