Ex situ catalytic upgrading of lignocellulosic biomass components over vanadium contained H-MCM-41 catalysts

H-V-MCM-41 catalysts containing 5, 10, and 30 wt% of vanadium were synthesized and applied to the ex situ catalytic pyrolysis (CP) of three polymeric components of lignocellulosic biomass for the first time. Characterization of the catalysts was performed using N₂ adsorption-desorption, XRD, FT-IR, and NH₃-TPD. The results of XRD analysis showed that 5 wt% and 10 wt% H-V-MCM-41 catalysts maintained the mesoporous structure, whereas the mesoporous structure was destroyed in 30 wt% H-V-MCM-41 with considerable amount of small V₂O₅ crystalline outside the framework. NH₃-TPD showed that H-V-MCM-41 has mostly weak acid sites and that 10 wt% H-V-MCM-41 had the largest quantity of acid sites due to framework vanadium. In the case of CP of cellulose using Py-GC/MS, 10 wt% H-V-MCM-41 showed the highest catalytic activity for the production of valuable furanic compounds such as furfural because of the enhanced deoxygenation over the acid sites formed on framework vanadium. In the case of CP of xylan as well, 10 wt% H-V-MCM-41 led to the largest yield of mono-aromatics. The production of acetic acid was also promoted by H-V-MCM-41 catalysts. The CP of lignin over H-V-MCM-41 catalysts promoted substantially the production of important feedstock chemicals for the petrochemical industry: phenolics and mono-aromatics.