Production of phenolics and aromatics by pyrolysis of miscanthus

Upgrading of the vapor-phase products from the pyrolysis of miscanthus was carried out over Al-MCM-41, Al-MCM-48, HZSM-5 and mesoporous MFI (Meso-MFI). The characteristics of the catalysts used in this study were analyzed using N2-sorption and NH3-TPD. The catalytic activities were evaluated in terms of deoxygenation and the products composition. Catalytic upgrading improved the quality of bio-oil through deoxygenation, although the yield of bio-oil was reduced due to cracking. Mesoporous Al-MCM-41, Al-MCM-48 and Meso-MFI were superior to microporous HZSM-5 in terms of the removal of oxygenates and in the production of phenolics. With respect to the production of aromatics, HZSM-5 and Meso-MFI were more effective due to their high acidity. Of the catalysts tested in this study, Meso-MFI showed the highest activity for the deoxygenation and aromatization. When Pt was loaded onto HZSM-5 and Meso-MFI, both cracking and dehydrogenation were promoted, resulting in enhanced deoxygenation and aromatization.