Catalytic pyrolysis of cellulose using zeolite synthesized from solid wastes based on solvent-free route

Biomass is the only renewable carbon-containing resource, which could be converted into high-value liquid fuel via catalytic fast pyrolysis (CFP) using zeolite catalysts. The development of ZSM-5 synthesis technology based on low-cost raw materials is crucial for industrial-scale production of ZSM-5 zeolites. In this study, we report a solvent-free route for synthesizing ZSM-5 zeolites from two solid wastes: spent fluid catalytic cracking (sFCC) catalyst and rice husk ash (RHA). The effect of ZSM-5 zeolites derived from various raw materials (individual RHA, sFCC catalyst, and their combination) on the conversion of cellulose into aromatics are investigated in a fixed bed reactor. Cellulose catalytic pyrolysis using the zeolite derived from the combination of RHA and sFCC catalyst (R/F-Zeolite) demonstrates a significant enhancement in the production of aromatics compared to using individual raw materials. When mixing 25% R/F-Zeolite with 75% commercial ZSM-5, the total yield of BTX (benzene, toluene, and xylene) increases by 16% compared to using individual commercial ZSM-5, with a 37% and 17% increase in the yield of benzene and toluene, respectively. Moreover, R/F-Zeolite has a better performance of coke resistance than commercial ZSM-5. This work offers a cost-effective solution for the industrial-scale synthesis of ZSM-5 zeolites to produce aromatic-rich biofuel, which also brings benefits in terms of waste disposal.