Catalytic pyrolysis of biomass with Ni/Fe-CaO-based catalysts for hydrogen-rich gas: DFT and experimental study

[Display omitted] •The Ea of RDS of critical reactions on NFC was decreased comparing with NC.•The toluene cracking is most likely to occur on NFC, while WGSR is the opposite.•The addition of Fe makes NFC have high catalytic activity and stability.•Compared with NC, NFC reduces Yliquid by 18.32% and increases Ygas by 26.27%.•The H2 yield was increased by 18.29% to 453.34 mL/g-biomass at 650 ℃ with NFC. The H2-rich gas produced by biomass pyrolysis with Ni-based catalysts were studied by DFT, thermodynamic simulation, and pyrolysis experiment. The complex reaction between volatiles of biomass pyrolysis was clarified through DFT calculation. The results proved that the Ea of key reactions for H2 production on Ni-Fe/CaO surface were lower than that on NC, which facilitates to produce H2. The order of the Ea of the rate determining step on Ni-Fe/CaO surface is toluene cracking reaction