Catalytic fast pyrolysis of cellulose over Ce0.8Zr0.2-xAlxO2 catalysts to produce aromatic hydrocarbons: Analytical Py-GC × GC/MS

Analytical pyrolysis-comprehensive two-dimensional gas chromatography/mass spectrometry (Py-GC × GC/MS) was employed for the on-line analysis of cellulose via catalytic pyrolysis with different catalysts and catalytic temperatures to study the products and aromatic hydrocarbons selectivity. The catalysts were subjected to characterization methods, including XRD , TEM , NH 3 -TPD, to investigate the effects of the physicochemical properties of the catalyst on the product distribution. Results showed that the Ce 0.8 Zr 0.2-x Al x O 2 could significantly promote the formation of aromatic hydrocarbons under 400–550 °C. A lower catalytic temperature (≤350 °C) favored the formation of furan compounds, and a higher catalytic temperature (≥450 °C) supported the formation of aromatic hydrocarbons. The relative peak area of the aromatics prepared by using the Ce 0.8 Zr 0.15 Al 0.05 O 2 catalyst was the highest being 85.24% at 550 °C. Moreover, the selectivity of the single-ring aromatics, such as benzene, toluene and xylene, were significantly affected by the presence of the Ce 0.8 Zr 0.2-x Al x O 2 catalysts. The higher total acidity of Ce 0.8 Zr 0.15 Al 0.05 O 2 favored the formation of benzene and toluene. Additionally, the Ce 0.8 Zr 0.15 Al 0.05 O 2 catalyst had a great thermal stability. The catalyst recycling tests showed that the Ce 0.8 Zr 0.15 Al 0.05 O 2 catalyst can be reused five times to produce aromatic-rich bio-oil via catalytic fast pyrolysis .