Effect of the nature of carbon support on the formation of active sites in Pd/C and Ru/C catalysts for hydrogenation of furfural

The study considered the formation and catalytic properties of the active sites in Pd/C and Ru/C catalysts supported on carbon nanotubes (CNT) and carbon black (CB). The nature of carbon support was shown to affect the dispersion of supported metal and its catalytic properties in the aqueous-phase hydrogenation of furfural. The 1.5% Pd/CB catalyst demonstrated a high selectivity (99%) for furfuryl alcohol during hydrogenation of furfural at a temperature of 50 °C and hydrogen pressure of 0.5 MPa. The 1.5% Pd/CNT catalyst was not active under mild conditions of the reaction (50 °C, 0.5 MPa), but had a greater tendency to reduce the furan ring under severe conditions (90 °C, 0.5 or 2.0 MPa) as demonstrated by an increased yield of tetrahydrofurfuryl alcohol. The ruthenium samples showed a low activity in aqueous-phase hydrogenation of furfural irrespective of the support nature and reaction conditions, possibly due to irreversible adsorption of water on the active sites.