Ventilation air methane (VAM) has an extremely low concentration, making its abatement exceptionally challenging. Catalytic oxidation offers a promising route for VAM treatment, but industrial application requires integrated catalysts with high activity and efficient mass transfer. In this study, a novel straight-channel NiO/CeO2 ceramic reactor was fabricated via mesh-assisted phase inversion, with NiO content systematically optimized to screen the optimal ratio. The 60 wt% NiO was the optimal composition, exhibiting excellent VAM oxidation performance. Brunauer–Emmett–Teller (BET) analysis confirmed that this optimal ratio yielded the largest specific surface area. Furthermore, H2-temperature-programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS) confirmed that this optimal ratio facilitated the formation of abundant NiO–CeO2 active interfaces, effectively inducing surface Ce3+ species and oxygen vacancies. These merits significantly enhanced the reactor’s oxygen adsorption capacity and redox properties, thus realizing efficient methane activation in catalytic oxidation. Moreover, the optimal reactor successfully passed 10 thermal cycle tests, further verifying the thermal stability of the catalytic structure. In addition, it exhibited outstanding long-term stability during a 100 h test, with no carbon deposition or active phase sintering observed. This work develops an optimized straight-channel NiO/CeO2 ceramic reactor and offers a practical and scalable design strategy for VAM oxidation.
Liu et al. (Thu,) studied this question.