WOx‐Modified Ni Catalyst Supported on Mesoporous Silica with Extra‐Large Mesopores for CO Methanation

A group of Ni–WO x /FDU‐12 ( x < 3; FDU‐12: Fudan University ordered mesoporous materials) catalysts is prepared via a polyhydroxy compound–assisted impregnation method for carbon monoxide (CO) methanation. Ethylene glycol is used as the solvent, and citric acid is added as the second polyhydroxy compound to enhance the dispersion of Ni 2+ ions. These polyhydroxy compounds are carbonized as sacrificial carbon via calcination in an inert atmosphere. Meanwhile, H 2 O is used as the reference solvent. These catalysts are systematically characterized by various techniques. The results show that the utilization of ethylene glycol and citric acid significantly reduces the size of Ni, and the addition of the WO x promoter further improves Ni dispersion. The optimal catalyst shows a high low‐temperature activity, which reaches thermodynamic equilibrium at only 360 °C and obtains the maximum CH 4 yield of 86.2% at 400 °C due to the fine Ni particle size and enhanced hydrogen chemisorption capacity. In addition, this catalyst shows high stability in a 100 h‐lifetime test at 400 °C, 0.1 MPa, and a high weight hourly space velocity of 60 000 mL g −1 h −1 . This is attributed to the synergistic effect of the WO 3 promoter and the physical barrier of carbon residue, as well as the confinement effect of FDU‐12 support.