Product regulation and catalyst deactivation during ex-situ catalytic fast pyrolysis of biomass over Nickel-Molybdenum bimetallic modified micro-mesoporous zeolites and clays

Abstract

Ni-Mo bimetallic modified micro-mesoporous zeolite catalysts were prepared and employed in the process of ex-situ catalytic fast pyrolysis (CFP) of poplar to produce liquid fuel. Clay catalysts were incorporated to further improve the products quality. The mass yield of monocyclic aromatic hydrocarbons (MAHs) increased under the catalysis of composite catalysts AZM and NiMo/AZM. HAP&Zeolite dual catalyst system reduced coke yield of NiMo/AZM to 5.01 wt%. Through real-time monitoring of gas products, the catalytic performance of zeolites began to decrease after the ratio of biomass and catalyst was more than 1. A series of characterization results futher demonstrated that AZM and NiMo/AZM possessed more stable catalytic ability and higher catalytic activity during the whole CFP process. N2 adsorption–desorption measurement and Raman characterization illustrated the formation and structure of coke, catalyst deactivation and the protective mechanism of mesopores on micropores.