Selective hydrogenation of 1,3-butadiene on molybdenum nitride catalyst: Identification of the adsorbed hydrocarbonaceous species

The hydrogenation of 1,3-butadiene has been studied on γ-Mo₂N catalyst. The γ-Mo₂N catalyst was found to be selective to hydrogenate 1,3-butadiene to 1-butene (selectivity is 87% at the conversion of 35% at 333 K). But the activity decreased gradually with reaction time. The surface species from 1,3-butadiene adsorption and reaction on molybdenum nitride were studied by IR and temperature-programmed surface reaction (TPSR) techniques. The presence of surface hydrocarbonaceous species was identified by both IR and H₂-TPSR. They cause the deactivation of the nitride catalyst and increase the selectivity to 1-butene in the hydrogenation of 1,3-butadiene. Their participation in the hydrogenation reaction is interpreted by means of hydrogen transfer.