Enhancement of hydrocarbon production and catalyst stability during catalytic conversion of biomass pyrolysis-derived compounds over hierarchical HZSM-5†
In order to promote hydrocarbon production and catalyst stability in catalytic fast pyrolysis (CFP) of biomass, HZSM-5 catalysts were treated with alkali solutions to introduce mesopores into the microporous system. Parent and hierarchical catalysts were tested in catalytic conversion of furan as an important intermediate from biomass fast pyrolysis (BFP). Controlled desilication with mole concentration of NaOH of 0.3 M resulted in sheet-like mesopores on the external sphere, enhancing mass transfer in the catalyst, and it specifically promoted the carbon yield of hydrocarbons by 21.6%. Though the coke content on these HZSM-5-0.3M catalysts increased gradually by 11.6%, the tolerance toward deactivation by coke deposition was improved. Cyclic tests of catalysis-regeneration process over hierarchical HZSM-5-0.3M over 20 cycles revealed that it can withstand long-running with a stable yield of hydrocarbons being achieved. Thus, hierarchical HZSM-5 is a suitable catalyst for CFP of biomass and its derivatives to hydrocarbons by this simple synthetic process.