Hydrogen production by methane steam reforming over Ru and Cu supported on hydrotalcite precursors

Abstract

Co6Al2 oxide was prepared using the hydrotalcite route. The obtained solid was thermally stabilized at 500 degrees C and then impregnated with 5 wt.% copper or 1 wt.% ruthenium nitrate solution followed by calcination at 500 degrees C under an air flow. X-ray diffraction results showed that the calcination of the impregnated solids led to the formation of various oxides (CuO, RuO2, CO3O4, CoAl2O4, CoAl2O4). The different impregnated and non impregnated solids were tested in the methane steam reforming reaction (MSR). Methane conversion did not exceed 5% at 800 degrees C in the case of the non impregnated solid, whereas the impregnation strongly enhanced the reactivity: similar to 89% and similar to 92% conversions were reached at 600 degrees C for Cu and Ru respectively. The good reactivity of ruthenium impregnated catalyst was attributed to the formation of easily reducible ruthenium and cobalt oxide species at the surface of the support. The addition of ruthenium made the reduction of surface and bulk cobalt oxides possible at lower temperatures.