K and Sr promoted Co alumina supported catalysts for the CO2 reforming of methane

K and Sr promoted Co alumina supported catalysts for the CO2 reforming of methane (973 K, CH4:CO2 (1:1)) have been prepared by the coimpregnation and successive impregnation methods. The catalysts (fresh and used (after reaction)) have been characterized using the following techniques: Atomic Absorption Spectroscopy (ICP-OES), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray (EDX) and Temperature Programmed Oxidation (TPO). The obtained results indicate that K is a more effective promoter than Sr and that the preparation method does not affect the catalyst performance. Because of that, the coimpregnation method (the simplest one) has been selected to prepare a series of K promoted catalysts with variable amount of potassium. It has been found that the amount of potassium influences both, the methane conversion and the amount of deposited carbon. The optimum amount of potassium seems to be around 0.6 wt.%, as the catalyst with this K loading presents a relatively high methane conversion (60%) and a quite low amount of deposited carbon (0.08% molar of the converted carbon) after 6 h reaction.