The hydrogenation of high-concentration monovinylacetylene over silica supported Pd-Pb bimetallic catalysts was investigated. It showed that the appropriate presence of Pb can prevent Pd nanoparticles from aggregation

hence facilitated the improvement of catalytic activity

i.e. the optimal molar ratio of Pb to Pd of 0.2. With the molar ratio of Pb to Pd above 0.2

Pd-Pb alloy can be formed

which causes catalytic activity loss. The positive correlation between the catalytic activity and the electron bonding energy of Pd 3d was manifested by X-ray photoelectron spectra. The temperature for PdO reduction exhibited a remarkable influence on the structure and the activity of the catalysts. The PdO reduction at 350℃ of the catalyst was incomplete thus with low activity. At 450℃ of the reduction temperature

it caused Pd nanoparticle sintering

hence with low activity and low butadiene selectivity. As a result

the optimal reduction temperature was 400℃. After 40 h

the catalyst was deactivated due to the blockage of pore by coke formation on catalyst surface. Subsequently

the improvement of anti-coking ability and the lifetime of the catalyst will be of interest.