Ex-situ catalytic co-pyrolysis of sawdust and municipal solid waste based on multilamellar MFI nanosheets to obtain hydrocarbon-rich bio-oil

摘要

In this study, H-type multilamellar MFI nanosheets (HMMN) were used for the catalytic reforming of municipal solid waste (MSW) and sawdust co-pyrolysis products to produce high-value bio-oil. Moreover, the catalytic deoxygenation performance of HMMN was studied. HMMN contains abundant surface area, mesopore volume, and a high ratio of Bronsted acid sites to Lewis acid sites. According to the results of thermogravimetric analysis (TGA), adding MSW improves the pyrolysis behaviors of sawdust by enhancing the escape of volatile matter. Analyzing the pyrolysis products reveals that a synergistic effect between sawdust and MSW promotes the formation of monocyclic aromatic hydrocarbons (MAHs) and reduces the relative yield of oxygen-containing compounds (OCCs), which facilitates further catalytic reforming for high-value bio-oil production. When the mass ratio of HMMN to sample is increased from 0% to 120%, the relative yield of MAHs increases from 15.64% to 53.5% (in 25%MSW), implying that HMMN exhibits high selectivity for MAHs. Furthermore, the content of OCCs is significantly reduced, with a maximum reduction of 58.2%. HMMN has a catalytic effect on the deoxygenation and aromatization of long-chain fatty acids and sugars. Relative to HZSM-5(38), HMMN exhibits higher aromatic hydrocarbon selectivity and a more significant inhibitory effect on the OCCs. Ex-situ catalytic reforming under HMMN is confirmed to be a feasible route to obtain hydrocarbon-rich bio-oil.