Enhanced generation of jet fuel-range aromatic hydrocarbons through catalytic pyrolysis of woody biomass by simple chemical treatment on ZSM-5 catalyst

Widespread reliance on fossil fuels and their increasing costs have necessitated the search for viable alternatives. This study details a reliable method for generating jet fuel-range aromatic hydrocarbons (C₈-C₁₆) via catalytic pyrolysis of woody biomass. To do this, HZSM-5 was modified using NaOH (N-HZSM-5) and HCl (H-HZSM-5) and utilized in the pyrolysis of three types of sawdust (S1, S2, and S3). In S1 pyrolysis, HZSM-5 increased C₈-C₁₆ aromatics’ selectivity despite a lower bio-oil yield compared to the Non-C test. Among sawdust samples, S2 pyrolysis produced the highest C₈-C₁₆ aromatics (44.2%) due to its compositional and thermal characteristics. The use of N-HZSM-5 in S2 pyrolysis maximized the yield of bio-oil (46.9 wt%) and the selectivity for C₈-C₁₆ aromatics (49.3 %). N-HZSM-5 exhibited stable performance over three cycles, with minimal decline in C₈-C₁₆ aromatics. This study proposes a sustainable and feasible method for the generation of biojet fuel from lignocellulosic biomass. Abbreviations: RJF, Renewable jet fuel; LAS, Lewis acid sites; BAS, Brønsted Lowry acid sites; S1, Sawdust 1; S2, Sawdust 2; S3, Sawdust 3; HZSM-5 (80), HZSM-5 (SiO₂/Al₂O₃: 80); N-HZSM-5, NaOH-treated HZSM-5 (80); H-HZSM-5, HCl-treated HZSM-5 (80); XRF, X-ray Fluorescence; XRD, X-ray diffraction (XRD); NH₃-TPD, Ammonia temperature-programmed desorption; FT-IR, Pyridine Fourier transform infrared; NMR, Solid-state nuclear magnetic resonance; MAS, Magic angle spinning; FE-SEM, Field emission scanning electron microscopy; HR-TEM, High-resolution transmission electron microscopy; S_BET, BET surface area; V_Total, Total pore volume; S_Meso, Mesopores’ surface area; V_Meso, Mesopores’ pore volume; S_Micro, Micropores’ surface area; V_Micro, Micropores’ pore volume; H⁺, Proton; Non-C, Non-Catalytic.