| Summary: | In order to reduce greenhouse gas emissions, which are reaching alarming levels in the atmosphere, capture, recovery, and transformation of carbon dioxide emitted to methane is considered a potentially profitable process. This transformation, known as methanation, is a catalytic reaction that mainly uses catalysts based on noble metals such as Ru and, although with less efficiency, on transition metals such as Ni. In order to improve the efficiency of these conventional catalysts, the effect of adding alkaline earth metals (Ba, Ca, or Mg at 10 wt%) and lanthanides (La or Ce at 14 wt%) to nickel (13 wt%), ruthenium (1 wt%), or both-based catalysts has been studied at temperatures between 498 and 773 K and 10 bar pressure. The deactivation resistance in presence of H<sub>2</sub>S was also monitored. The incorporation of La into the catalyst produces interactions between active metal Ni, Ru, or Ru-Ni and the alumina support, as determined by the characterization. This fact results in an improvement in the catalytic activity of the 13Ni/Al<sub>2</sub>O<sub>3</sub> catalyst, which achieves a methane yield of 82% at 680 K for 13Ni/14La-Al<sub>2</sub>O<sub>3</sub>, in addition to an increase in H<sub>2</sub>S deactivation resistance. Furthermore, 89% was achieved for 1Ru-13Ni/14La-Al<sub>2</sub>O<sub>3</sub> at 651 K, but it showed to be more vulnerable to H<sub>2</sub>S presence.
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