Microwave-assisted hydrothermal synthesis of Ru/CeO2 catalyst for efficient and stable low-temperature dry reforming of methane

Abstract

As the widely applied catalysts in dry reforming of methane (DRM), Ni-based catalysts typically suffer from severe coke formation on the catalyst leading to the deactivation of the catalyst. Meanwhile, with great trends of reducing the operating temperature for DRM reactions, the Ni-based catalysts can’t exhibit comparable reactivity in low-temperature DRM reactions. To reduce coke formation and achieve better reactivity at low temperatures, a novel Ru/CeO2 catalyst was synthesized through a microwave-assisted hydrothermal method and exploited in a low-temperature DRM reaction in a fixed bed reactor. It exhibited comparable activity of above 58 % CH4 and 71 % CO2 conversion with above 0.85 H2/CO ratio for over 120 h at 600 °C. Moreover, it remained stable without obvious coke deposition on the catalyst after the long-term experiment. The characterizations by XRD, XPS, HAADF-STEM, FTIR and some temperature-programmed experiments indicated that microwave irradiation and the introduction of glucose played important roles in achieving great thermal stability and better DRM reactivity of Ru/CeO2. Ru, as the active metal compared with Ni, exhibited moderate CH4 dissociation ability leading to excellent coke resistance. The novel Ru/CeO2 catalyst with high DRM reactivity, simple synthesis method and great coke resistance in this work offers a new opportunity for the commercialization of low-temperature DRM reaction.