CO Methanation on Mesoporous Ni–VOx/FDU‐12 Catalyst: Effects of the VOx Promoter on Low‐Temperature Activity

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Herein, a series of Ni–VOx/FDU‐12 catalysts are prepared by an incipient impregnation method with FDU‐12 (cubic, Fm‐3m) as the support. The samples are characterized by nitrogen adsorption, X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, H2‐temperature programmed reduction, and X‐ray photoelectron spectroscopy. Among all catalysts, Ni–VOx/FDU‐12 with NiO of 10 wt% and V2O5 of 2 wt% (10N2VF) show the best catalytic performance, which reaches maximum CO conversion and CH4 yield of 99.4% and 89%, respectively, at 325 °C. The lifetime test is conducted at a constant temperature of 450 °C for 100 h at 0.1 MPa and a high weight hourly space velocity (WHSV) of 60 000 mL g−1 h−1. The 10N2VF exhibit high antisintering and coking properties. The addition of the vanadium promoter improve Ni dispersion and change Ni electron density, which enhance the low‐temperature ability for CO dissociation via the weakening of CO linkage. In contrast, a large number of oxygen vacancies formed by the oxidation–reduction cycle of V5+/V4+/V3+ can enhance the dissociation of the by‐product CO2 and generate oxygen intermediates, which prevent carbon deposition on the surface of Ni particles.