Characterization and hydrodeoxygenation properties of Co promoted Ni-Mo-B amorphous catalysts: influence of Co content

Different contents of promoter (Co) in Co-Ni-Mo-B amorphous catalysts were prepared by chemical reduction of the precursors of metal salts with a sodium borohydride aqueous solution. The catalysts were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Adding a proper content of the promoter Co into Ni-Mo-B amorphous catalyst could increase the MoO2 content and decrease the particle size, but doping excess Co would cover some of the active sites and increase the particle size of the catalysts. The effect of Co content on the catalytic hydrodeoxygenation activity of the amorphous catalysts was studied using phenol as a model compound. The main route for the HDO of phenol on these amorphous catalysts was hydrogenation-dehydration and the content of aromatic compounds in HDO products was decreased obviously. The pseudo first-order reaction rate constant of the phenol HDO on Co-Ni-Mo-B amorphous catalyst was much greater than that of MoS2 when adding proper promoter Co.