Evaluating Pd-Ni layered catalysis for selective hydrogenation of 1,3-butadiene: A theoretical perspective

GUILLERMINA GOMEZ, PATRICIA G. BELELLI, GABRIELA F. CABEZA, NORBERTO J. CASTELLANI

JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2014 vol. 394 p. 151 - 161

1381-1169

The partial hydrogenation of 1,3-butadiene (13BD) to several C4H8products, including 1-butene (1B),2-butene (2B) and butan-1,3-diyl (B13R), on both Pd/Ni(111) and Pd3/Ni(111) bimetallic surfaces wastheoretically investigated using DFT methods. For that purpose, different intermediates C4H7 and C4H8 radical species were evaluated according to the Horiuti?Polanyi mechanism performed in two sequentialsteps. The whole process was found to be exothermic on Pd/Ni(111) and endothermic on Pd3/Ni(111). Furthermore, the former surface, where the intermediate adsorptions are more favorable, exhibits loweractivation barriers than Pd3/Ni(111). On both surfaces, the B13R formation is associated with high tran-sition state energies through the pathways studied here; for this reason, it is extremely improbable toobtain B13R. Our calculations predict that on the Pd/Ni(111) catalyst model, the products would bemainly the butene isomers, with a little more selectivity toward 2B, in contrast to the pure Pd surfaceand in agreement with experimental data.