MOF-derived NiM@C catalysts (M = Co, Mo, La) for in-situ hydrogenation/hydrodeoxygenation of lignin-derived phenols to cycloalkanes/cyclohexanol

MOF-derived Ni-based bimetallic catalysts were found to be effective for the in-situ hydrogenation/hydrodeoxygenation of lignin-derived monophenols and dimers with isopropanol as the hydrogen-donor solvent (without external hydrogen). The synergistic effects of bimetallic catalysts were studied, and their catalytic properties afforded the best conversion rate of phenols and cyclohexanol/cycloalkane yields. The detailed physicochemical characterization was conducted by means of XRD, H-2-TPR, NH3-TPD, and pyridine-IR analysis. The effects of reaction temperature (200-260 degrees C) and reaction time (2-5 h) on the performance of lignin-derived monophenols and dimers were investigated. During the in-situ hydmgenation/hydrodeoxygenation of lignin-derived phenols, the steric effects and the effects of various functional groups, notably methoxy groups, were investigated. In-situ conversion of lignin-derived phenols with isopmpanol was achieved over different Ni/M ratios of NiM@C (M = Co, Mo, and La) catalysts, from which NiLa0.33@C produced satisfactory yields of cyclohexanol/cycloalkanes.