Liquid-phase selective hydrogenation of phenol to cyclohexanone over the Ce-doped Pd–B amorphous alloy catalyst

Abstract Ce-doped Pd–B amorphous alloy catalysts were prepared by chemical reduction of mixed PdCl 2 and Ce(NO 3 ) 3 with KBH 4 . During liquid-phase selective hydrogenation of phenol to cyclohexanone, the as-prepared Pd–Ce–B catalysts exhibited much higher activity, better selectivity and excellent durability than the undoped Pd–B. Based on various characterizations, the promoting effect of Ce-dopant on the catalytic properties can be addressed as follows: (1) stabilizing the amorphous structure of Pd–B alloy and enhancing the dispersion degree of Pd active sites; (2) increasing the electron density of Pd, which could enhance hydrogenation activity and improve catalytic durability; (3) increasing the surface basicity, which facilitated the non-planar adsorption of phenol on catalyst surface, leading to higher cyclohexanone selectivity.