Supported bimetallic catalysts Pd-M/CeO2(M=Fe, Co, Cu) were prepared by the impregnation method and the liquid phase catalytic hydrodechlorination (HDC) of 2,4-dichlorophenoxyacetic acid (2,4-D) was investigated over these catalysts. The catalysts were characterized by inductive coupled plasma optical emission, scanning electron microscope, X-ray photoelectron spectrometer and CO chemisorption. The results showed that cerium oxide could effectively disperse metal particles, and the synergy between metals improved catalytic performance. The Pd-Fe bimetallic catalyst has a relatively excellent catalytic effect. The catalytic activity of Pd-Fe/CeO2 increased first and then decreased with the increase of Fe loading. In addition, the dechlorination of 2,4-D were proceeded via both the stepwise and concerted pathways.
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