(205e) Catalytic Hydropyrolysis of Beetle-Killed Trees for the Production of Transportation Biofuels

In this study, we conducted catalytic hydropyrolysis experiments on beetle-killed trees such as Pine, Ash borer and Red bay. The experiments were performed using a micro pyrolyzer-Py/GC-MS setup. This study focused on the hydropyrolysis of beetle-killed trees in the presence of various heterogeneous catalysts like HZSM5, NiMo-HZSM5, and NiRe-HZSM5. We investigated the effects of different process parameters such as temperature, catalyst-to-biomass ratio, and hydrogen partial pressure on product yield. Our findings suggest that across the three feedstocks, temperature, pressure, and catalyst-to-biomass ratio play crucial roles in producing aromatics essential for transportation biofuel. The influence of catalyst acidity on product yields was also reported in this work and we observed that increasing the acidity of the catalyst positively influences hydrocarbon yield, irrespective of the feedstocks. Additionally, we examined the effect of acidity on the aromatic distribution of the product, revealing a more pronounced yield of C7 and C8 carbon numbers with increasing acidity. NiMo-HZSM5, and NiRe-HZSM5 have the potential to produce hydrocarbons for transportation biofuel as a result of the synergistic effect of metals doped on HZSM-5. Although we hypothesized that Re is a better alternative compared to Mo-containing zeolites because of its higher catalytic performance and stability compared to Molybdenum, the results we obtained with NiRe-HZSM-5 showed otherwise as we obtained only a small yield of alkanes compared to NiMo-HZSM-5. Additionally, we utilized response surface methodology, a blend of mathematical and statistical technique to optimize the various operating conditions for achieving the best yield. Our analysis revealed that the maximum bio-oil yield of 35% occurred at 570℃, 13.79 bar, and catalyst to biomass ratio of 13.9:1; an optimal aromatic yield of 28.3% was observed at 562℃, 13.79 bar, and catalyst to biomass ratio of 13:1 and finally, optimal alkane yield of 5.7% was achieved at 400℃, 13.79 bar, and catalyst to biomass ratio of 8.6:1