Investigation of perovskite BaCe1-xMnxO3-δ for methane combustion

Abstract

The Mn-doped BaCeO3 series composite oxide catalysts were prepared by a sol-gel method. The low-temperature catalytic methane combustion activity test of BaCe1-xMnxO3-δ series composite oxide catalysts at low temperature (200-600 °C) was studied in a fixed bed reactor. The physical properties of the catalyst were characterized by XRD, SEM, particle size analysis and specific surface area measurement, and the conductivity of the sample was measured by AC impedance spectroscopy. Research shows that: the perovskite phase composite oxide catalyst was successfully prepared by the sol-gel method, and the prepared perovskite phase catalyst has good catalytic performance and high temperature stability. The catalytic performance of the catalyst changes with the conductivity, which shows a proportional relationship; when the temperature is lower than 650 °C, Mn doping significantly improves the catalytic activity of the BaCeO3 catalyst for methane combustion. The catalytic activity increases initially and then decreases with the doping amount of Mn. When the doping amount is 0.4 the catalyst has the best catalytic activity, with the ignition temperature of methane at as low as 249.7 °C, and the catalytic methane complete conversion temperature T90 (The corresponding temperature when CH4 conversion rate is 90%) at 423.2 °C. This work is of considerable referential importance in the optimization design of catalysts for CH4 combustion at low temperature.