Switchable production of aromatics and alkanes by Ni-ReOx/CeO2-catalyzed wood depolymerization.

• Ni-ReO x /CeO 2 was designed for switchable conversion of lignocellulose into aromatics and alkanes. • A strong electronic interaction and synergic effects of Ni and ReO x species in Ni-ReO x /CeO 2 was disclosed. • Direct transformation of lignocellulose avoids the pretreatment process and achieves utilization of all three components. • The catalyst can be reused by simple magnetic separation. Complete conversion of lignocellulosic biomass into chemicals and fuels is particularly attractive in biorefinery concept while remains a great challenge due to complicated structure of lignocellulose and its notorious resistance to chemical transformation. Herein, a recyclable multifunctional Ni-ReO x /CeO 2 catalyst was designed for switchable conversion of lignocellulose to either aromatics or liquid fuels by simple tuning reaction parameters. Under the condition of 200 °C, 1 MPa H 2 , lignin in woody biomass was deconstructed via lignin-first manner to produce aromatic oil with the mass yield up to 88.4 %, leaving cellulose and hemicellulose intact. Under harsher condition (260 °C, 4 MPa H 2), complete conversion of lignocellulose to alkanes was achieved in 43.8 % carbon yield. The control experiments and characterization of the catalyst revealed that ReO x species of Ni-ReO x /CeO 2 enhanced Ni dispersion, the strong electronic interaction and synergic effects of Ni and ReO x species played major roles for the flexible transformation. [ABSTRACT FROM AUTHOR]