Dry reforming of methane over Co-Ce-M/AC-N catalyst: Effect of promoters (Ca and Mg) and preparation method on catalytic activity and stability

Abstract The catalytic activity of DRM reaction over 1M-1Co-1Ce/AC-N (M = Ca and Mg) catalysts was investigated at 800 °C and under atmospheric pressure. By promoting N-doped activated carbon supported Co-Ce catalysts with alkaline-earth metals to obtain catalysts with better catalytic performance is the main purpose of study. The catalysts were prepared by wet-impregnation method and the influence of impregnation sequence on catalytic performance was also studied. The characterization was conducted using TPR, TPD, XPS, TEM and Raman. The catalyst 1Ca-1Co-1Ce/AC-N promoted with Ca and prepared by co-impregnation exhibited higher catalytic activity than unmodified. This was mainly due to the stronger interaction between metal and support as well as better active metals dispersion. The 1Ca-1Co-1Ce/AC-N catalysts also displayed excellent stability and XPS results indicated that higher Ce 3+ /Ce 4+ and O β /(O α +O β ) ratios were observed on this catalyst. However, the catalyst 1Co-1Ce/1Ca/AC-N prepared with sequential impregnation exhibited poor stability. In addition, the TEM of the spent catalysts revealed that there were a large number of carbons were generated on active metal surface.