The selective cleavage of C–O linkages and efficient hydrogenation over a cobalt-doped nickel phosphide catalyst

Abstract

The catalytic hydrogenolysis of lignite and its derivatives into liquid fuels and high-value-added chemicals represents a promising route for the efficient utilization of fossil-based organic resources. Here, a series of Co-doped Ni₁₂P₅ (x% Co–Ni₁₂P₅) catalysts were successfully synthesized via a solvothermal strategy for the catalytic hydrogenolysis of the C–O linkages in lignite model compound benzyl phenyl ether (BPE). The 3% Co–Ni₁₂P₅ catalyst exhibited an excellent catalytic hydrogenolysis performance, obtaining nearly 100% conversion of BPE under the conditions of 160 °C, 1.5 MPa H₂, and 1 h. Based on characterization results, the high catalytic activity of the 3% Co–Ni₁₂P₅ catalyst was attributed to Ni^δ+ species owing to the electron transfer from Co to Ni and P which provided plentiful Lewis acid sites and Brønsted acid sites. It was these factors that greatly accelerated H₂ dissociation and optimized the C–O linkage adsorption energy of BPE to −5.87 eV, enabling efficient hydrogenolysis of the C–O linkage. This work could provide some useful insights for the catalytic hydrogenolysis of lignite and its derivatives in the future.