ИСТИНА

Our research was focused on the preparation of Pd1-In1/Al2O3 catalyst containing Pd1In1 intermetallic nanoparticles for selective acetylene hydrogenation. The choice of PdIn composition was motivated by its high selectivity in liquid-phase substituted alkyne hydrogenation discovered previously. Formation of Pd1-In1 structure was confirmed by XRD data due to the appearance of characteristic signal with the maximum at 20~39.2°. The CO-DRIFTS data revealed the presence of Pd1 centers isolated by indium atoms on the surface of PdIn nanoparticles. The catalyst performance was studied in the gas-phase hydrogenation of acetylene in ethylene-rich feed (1.09%C2H2/C2H4). The data obtained suggest that the favourable characteristics of intermetallic catalyst in gas-phase acetylene hydrogenation stems from three factors: (1) the isolation of the Pd1 active sites in the crystal structure with In atoms (site-isolation structure), (2) the strong alteration of the electronic structure of Pd1-In1 particles in comparison to elemental Pd, and (3) the suppression of Pd-hydride formation shown by the H2-TPD method.