Sustainable Aromatics for Aviation: Targeted Pathways for Complete Blend of Aviation Fuel

Abstract Sustainable aviation fuel (SAF) has become a strategic goal for global aviation decarbonization. However, the transition of the conventional jet fuel toward higher-blend and fully formulated SAF remains challenging. Aromatics are a critical component and/or additive in jet fuel, owing to their capability for increasing fuel density, elastomer compatibility, and combustion performance. Lignocellulosic biomass, waste plastic, waste oils, and sugar-derived furanics are outstanding candidates for sustainable aromatics for SAF, but the conversion techniques of those feedstocks remain premature. This critical review provides a centralized framework evaluating those waste-to-aromatics methods under both thermochemical and biochemical pathways. Fast pyrolysis, hydrothermal liquefaction, catalytic cracking, reductive depolymerization, microbial depolymerization, and enzymatic conversion are compared by exercising common criteria (i.e., operating conditions, product distribution, aromatic selectivity, and technological maturity, etc.). Based on the past majority of reviews that evaluate pathways over inconsistent system boundaries, functional units, and assumptions in life-cycle and techno-economic assessments, this work brings pathway comparisons into a centralized framework for sustainable aromatic and SAF-relevant hydrocarbon production. We have paid particular attention to catalyst deactivation and regeneration, hydrogen utilization in hydrodeoxygenation, and the distinction between producing aromatic intermediates and subsequent upgrading to an ASTM-approved aviation fuel blendstock. With the insights guiding potential future research, the produced aromatic SAF candidates could serve as a missing piece of the puzzle to complete SAF blending in modern jet engines.