H₂ production from catalytic steam reforming of n-propanol over ruthenium and ruthenium-nickel bimetallic catalysts supported on ceria-alumina oxides with different ceria loadings

Catalytic steam reforming of n-propanol was investigated over ruthenium and ruthenium-nickel bimetallic catalysts supported on ceria-alumina oxides with different ceria loading (0-10% CeO₂ wt/wt). Catalysts were characterized by BET surface area analysis, powder X-ray diffraction, temperature programmed reduction and energy dispersive X-ray analysis with scanning electron microscopy. Steam reforming activity was tested in a fixed bed tubular flow reactor at 450 or 500 °C using a feed of n-propanol/water mixture at a molar ratio of 1:12 and a constant liquid feed rate of 0.1 ml min^-1. The effluent gas was monitored by GC/TCD and the evolution of the rate of hydrogen formation and the product gas distribution as a function of time was studied. Calcination in air after the impregnation with RuCl₃ was found to reduce ruthenium dispersion and lower steam reforming activity. Both high metal loading and sufficient ceria promotion are essential for active and stable performance. Otherwise, dehydration reaction dominates and catalyst deactivation became severe. Catalysts with 3 wt% Ru, 10 wt% Ni and 3 or 10 wt % ceria were found to be very reactive and stable at both 450 and 500 °C.