Zr‐promoted nickel‐rich spinel‐supported Ni catalysts with enhanced performance for selective CO methanation

Summary CO selective methanation (CO‐SMET) is an efficient hydrogen purification technology for proton exchange membrane fuel cells. The development of nonnoble metal–based catalysts is quite essential and imperative for CO‐SMET and has received considerable interest. Herein, a Zr‐promoted nickel‐rich spinel‐supported Ni catalyst (Ni‐ZrO2/NiAl2O4) was acquired by an epoxide‐driven sol‐gel process and associated co‐impregnation method. The usage of ZrO2 could enhance the reducibility of the Ni oxides and promote the formation of small Ni particles size, then effectively increase the sorption capacities for both H2 and CO and facilitate the CO dissociation from catalyst surfaces. All these endowed the catalyst with excellent catalytic performance for CO‐SMET, which could lower the CO outlet level to less than 10 ppm with the selectivity higher than 50% within a large temperature window (185°C‐255°C). Additionally, the catalyst was highly stable with no obvious carbon deposition or performance degradation during the long‐term stability test. This work offers a new technical route to build highly efficient nickel‐rich spinel‐supported catalysts in the production of high‐quality hydrogen. Highly efficient Zr‐promoted nickel‐rich spinel‐supported Ni catalyst was successfully synthesized and employed in CO selective methanation for hydrogen‐rich gas purification. ZrO2 species effectively increased the sorption capacities for both H2 and CO and facilitated the dissociation of CO in the catalyst surfaces. The catalyst displayed high catalytic activity, selectivity in a wide low‐temperature window, and showed good stability and strong anticoking ability.