Selective hydrodeoxygenation of guaiacol to cyclohexanol over core-shell Cox@C@Ni catalysts under mild condition.

Guaiacol, a typical lignin-derived phenolic compound, can be converted to high value-added cyclohexanol through hydrodeoxygenation (HDO). In this work, a series of core-shell Co x @C@Ni catalysts were prepared via two-step hydrothermal and calcination treatments, and applied to catalyze guaiacol to cyclohexanol. Compared with Co@C catalyst, core-shell Co x @C@Ni catalysts exhibited much better catalytic performance. Almost 100% guaiacol conversion and 90% cyclohexanol selectivity were achieved over Co 1.2 @C@Ni catalyst at 220 °C, 0 MPa N 2 for 2 h using isopropanol as H-donor solvent, which was carried out under much milder conditions compared with previous research. The structure feature of core-shell Co x @C@Ni catalysts were analyzed by BET, XRD, SEM, TEM, HRTEM, etc. The catalyst compositions and acidities played a significant role on hydrodeoxygenation of guaiacol via ICP and NH 3 -TPD analysis. The influences of reaction temperature, reaction time and initial nitrogen pressure were also investigated to explore the optimal reaction condition. Moreover, the possible reaction pathways and reaction mechanism was deduced based on the product distributions and physicochemical properties. Core-shell Cox@C@Ni catalysts were synthesized for catalytic hydrodeoxygenation of guaiacol to generate cyclohexanol under mild condition. [Display omitted] • Guaiacol can be effectively converted into cyclohexanol over core-shell Cox@C@Ni catalysts. • The highest 90% cyclohexanol yield was obtained over Co1.2@C@Ni at 220 ℃, 0 MPa N2 for 2 h. • The synergetic effect of Co and Ni and the acidity of catalysts play an important role in the HDO of guaiacol. • A possible reaction mechanism of hydrogenation process was studied. [ABSTRACT FROM AUTHOR]