Hydrogenation of 1,3-butadiene over catalysts prepared from amorphous Pd2Ni50Nb48 ribbon: Effect of self-poisoning on competitive adsorption Original Research Article

Hydrogenation of 1,3-butadiene was investigated on catalysts prepared from an amorphous ribbon of composition Pd2Ni50Nb48, activated by oxygen and hydrogen treatments at 683 K. The hydrogenation activity of the sample decreased gradually with time, indicating formation of carbonaceous materials (oligomers). As a consequence of oligomer formation the butene selectivity remained constant even at 100% butadiene conversion. Apparently n-butenes could not compete with oligomers. Restart experiments confirmed that diene, due to its high strength of complexation, is able to adsorb on metallic sites in the presence of oligomers. The results emphasize the role of oligomers in selective semihydrogenations.