Effect of cobalt promotion on hydrotalcite-derived nickel catalyst for CO2 methanation

A series of cobalt-promoted Ni-Mg-Al hydrotalcite-derived catalysts were tested towards CO2 methanation reaction. The best among examined was the one with 1 wt% cobalt in fresh hydrotalcite, obtaining 77% conversion and 99% CH4 selectivity at 300 °C. Above that temperature, catalyst working with-near-equilibrium parameters. It also stable for up to 24 h on stream. Other cobalt-containing samples likewise very active selective during time Due use a low amount (0.5–4 wt%) Co-Ni alloy not subject research – both materials formed probably solid solution nickel matrix. Although behavior as textural electronic promoter confirmed. Co found improve reducibility species, hydrogen uptake, acidic/basic properties by increasing number medium strength strong basic sites. Tendency sintering crystallites confirmed this study, however, increased content Co, bigger metal under reduction conditions.