Comparing Co‐catalytic Effects of ZrOx, SmOx, and Pt on COx Methanation over Co‐based Catalysts Prepared by Double Flame Spray Pyrolysis

The impact of different co‐catalytically acting promoters (Pt, ZrO x and SmO x ) during CO x methanation was investigated on alumina supported Co‐based model catalysts. To obtain samples with identical structure and morphology independent of the presence and the type of promoter added, double flame spray pyrolysis was employed for the synthesis, which, in contrast to classical catalyst preparation techniques, allows controlling and separating the particle formation processes of the different catalyst components. In this way, differently promoted and unpromoted catalysts with identical size distributions and dispersions could be synthesized to study co‐catalytic effects in isolation. For CO 2 methanation, all promoters led to improved methanation yields and long‐term activities within the whole temperature range as compared to the unpromoted catalyst. Among them, zirconia and platinum performed best. In case of CO methanation, a beneficial influence of the studied promoters could also be verified – with Pt showing the best results. Yet, all catalysts deactivated rapidly above 310 °C, limiting their usability to lower temperatures.