Large-pore mesoporous RuNi-doped TiO2–Al2O3 nanocomposites for highly efficient selective CO methanation in hydrogen-rich reformate gases

Abstract

A series of large-pore mesoporous RuNi-doped TiO2–Al2O3 nanocomposites were prepared by a facile sol–gel method using a one-pot protocol based on evaporation-induced self-assembly. Owing to high density of active sites, an open nanoarchitecture and highly promotional efficiency by synergetic effects, the as-prepared nanocomposites demonstrated excellent catalytic properties in selective CO methanation (CO-SMET). The final concentration of CO can be reduced to less than 50ppm with more than 50% selectivity over the MRNAT-30Ni catalyst. The working temperature window covered the typical working range of 200–250°C in conventional upstream low-temperature shift reactors. The MRNAT-30Ni catalyst has excellent stability during 200h time on stream with no detectable change in CO and CH4 concentrations, and CO in outlet reaches level below 20ppm under realistic reaction conditions. This remarkable improvement of activity/selectivity and stability could lead to wide implementation of this one-pot protocol for the synthesis of large-pore mesoporous nanocomposite catalysts for the CO-SMET process.