Synergistic catalytic hydrogenation of phenol over hybrid nano-structure Pd catalyst

Abstract

Pd-based catalyst is one of the most widely used catalysts in the selective hydrogenation of phenol. Herein, a new strategy has been developed to fabricate a hybrid nano-structure Pd catalyst. By coating ZrO2 on the activated carbon(AC), then anchored Pd nanoparticles on the ZrO2/AC, a hybrid nano-structure Pd/@-ZrO2/AC catalyst with strong synergy can be obtained. The results show that the Pd/@-ZrO2/AC catalyst exhibited a synergistic effect and remarkable catalytic activity in the selective hydrogenation of phenol, outperforming both conventional Pd/ZrO2 and Pd/AC catalyst. Importantly, the catalytic activity was closely related to the calcination temperature of ZrO2/AC. The ZrO2/AC support was calcined at 500℃ with a minimum particle size, which enables Pd nanoparticles to support on it with high dispersion. Then the Pd/@-ZrO2/AC(500) exhibited stronger interaction of Pd nanoparticles with the ZrO2/AC surface as compared to other catalysts and shown the highest catalytic activity. Moreover, a series of this hybrid nano-structure Pd/@-MexOy/AC catalysts(MexOy: TiO2, CeO2, La2O3) have been synthesized and further confirmed the synergistic effect in the selective hydrogenation.