Influence of carbon nanomaterials on the properties of Pd/C catalysts in selective hydrogenation of acetylene

Palladium was deposited on carbon nanotubes and two types of carbon nanofibers to study the effects of the carbon support. The state of finely dispersed Pd particles deposited on the carbon nanomaterials was studied by physical methods and it was found that the crystallographic structure of the carbon support affects the properties of the active component. Stabilization of the most finely dispersed palladium was observed on carbon nanofibers with a stack structure in comparison with other carbon supports. Decrease of the concentration of supported palladium on the carbon nanofibers with the stack structure below 0.2 wt.% led to stabilization of the metal in the atomic state. Palladium in the atomic state in Pd/C catalysts demonstrated the highest selectivity in conversion of acetylene hydrogenation to ethylene. Doping of carbon nanofibers by nitrogen atoms substantially alters the properties of supported Pd catalysts by decreasing activity of the catalysts while their selectivity increases.