Optimizing the Aromatic Yield via Catalytic Fast Co-pyrolysis of Rice Straw and Waste Oil over HZSM-5 Catalysts

Catalytic fast pyrolysis (CFP) of lignocellulosic-based feedstocks into aromatics has attracted much interest, owing to its economic feasibility. However, the low effective hydrogen index (H/C-eff) of lignocellulosic biomass adversely impacts the production of aromatics via CFP. Here, we report catalytic fast co-pyrolysis (CFCP) of hydrogen-deficient rice straw (an important lignocellulosic-biomass-derived feedstock) coupled with hydrogen-rich stearic acid, gutter oil, or microalgae oil over a series of selected HZSM-5 catalysts. The aromatic yield of CFP of these three reactants decreases slightly in the order of stearic acid, microalgae oil, and gutter oil. CFP of rice straw has a lower aromatic yield than CFP of stearic acid, gutter oil, or microalgae oil. However, CFCP of rice straw along with each of the hydrogen-rich candidates produces higher aromatic yields than predicted by the theoretical yield values of CFP of the individual materials. Additionally, the mass ratios of the two reactants are optimized to improve the aromatic yield.