Enhancement of aromatics production via cellulose fast pyrolysis over Ru modified hierarchical zeolites

In the present study, Ru modified hierarchical zeolites xRu-MZSM were developed for cellulose fast pyrolysis. Comprehensive catalyst characterizations including XRD, XPS, N-2 adsorption-desorption, Py-IR and so on, were performed to unveil the essential structural properties. The chemical modification and Ru decoration remarkably regulated the distribution of Bronsted/Lewis acid sites. The presence of RuOx species would supply abundant strong Lewis acid sites for participating catalytic cracking, dehydration, decarbonylation, decarboxylation, cyclization, aromatization, etc., in cooperation with Bronsted acid sites. In-situ generated active Ru-0 centers during cellulose pyrolysis might facilitate the proceeding of deoxygenation, hydride transfer, and dehydrogenation. Among the as-prepared catalysts screened, 2Ru-MZSM was much more efficient in aromatics production from cellulose fast pyrolysis compared to parent ZSM, wherein the total aromatics yield achieved 16.8% at temperature of 650 degrees C and heating rate of 10 degrees C/ms with corresponding E value as low as 23.40 kJ/mol. Also, plausible reaction mechanism for xRu-MZSM involved cellulose fast pyrolysis was proposed in detail. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

In this study, Ru modified hierarchical zeolites were developed for cellulose fast pyrolysis, showing improved efficiency in aromatics production. The comprehensive characterization of the catalysts revealed their essential structural properties, and the presence of active Ru-0 centers facilitated key reactions. Among the screened catalysts, 2Ru-MZSM exhibited higher aromatics yield.