International Journal of Hydrogen Energy, Vol.44, No.36, 20007-20016, 2019
Ca-Al layered double hydroxides-derived Ni-based catalysts for hydrogen production via auto-thermal reforming of acetic acid
Biomass-derived acetic acid (HAc) is an alternative resource for hydrogen production, and heat self-sustained auto-thermal reforming (ATR) of HAc shows potential for practical application, while robust and stable catalysts remain as a key factor. Ca-Al layered double hydroxides (LDHs)-derived Ni-based catalysts were synthesized by co-precipitation, and tested in ATR of HAc for hydrogen production. Over the LDHs-derived Ca2.55Ni0.45AlO4.5 catalyst, active sites of Ni-CaO-Ca12Al14O33 were formed, and interaction among Ni, CaO and Ca12Al14O33 was proved to be a pivotal role for 1) thermal stability, 2) resistance to oxidation of Ni-0 species, and 3) inhibiting coke deposition through catalytic cycle, CaO + CO2 <-> HCaCO3 and CaCO3+*C <-> CaO+2CO, for gasification of coking precursors. Hence, the Ca2.55Ni0.45Al04.5 catalyst showed enhanced activity with no obvious deactivation in ATR: the acetic acid conversion rate was 100%, and the hydrogen yield remained stable near 2.75 mol-H-2/mol-HAc at a rate of 40.34 mmol-H-2/s/g-catalyst. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.