Influence of surface support properties on the liquid-phase selective hydrogenation of phenylacetylene on supported nickel catalysts

The role of textural and acid-base properties of supports on metal-support interaction effects has been evaluated through the results obtained in the liquid-phase selective hydrogenation of phenylacetylene carried out on 20 wt% supported nickel catalysts. SiO2, Al2O3, AlPO4, active carbon and a natural sepiolite were used as supports. The effects of Ni-Cu alloying were also studied. The relative adsorption constants, K-T,K-D, and the relative reactivities, R-T,R-D. obtained in the consecutive hydrogenation process, were used to follow the effects of any electron transfer between the nickel atoms and acid-basic sites on the support surface. Structural defects of supported nickel crystallites were determined by X-ray diffraction line broadening analysis and used for measuring the participation of geometric effects of supported nickel crystallites in the catalytic activity. Results obtained may be better explained within a framework of simultaneous electronic and structural metal-support interaction effects.