(544cb) Synthesis, Characterization, and Application of Ruthenium-Doped SrTiO3 Perovskite Catalysts for Microwave-Assisted Methane Dry Reforming

A series of ruthenium-doped strontium titanate (SrTiO₃) perovskite catalysts were synthesized by conventional and microwave-assisted hydrothermal methods. The structure was analyzed by X-Ray diffraction (XRD) confirming the formation of the perovskite phase with some TiO₂ anatase phase in all the catalysts. Microwave irradiation decreases the temperature and time of synthesis from 220 °C for 24 h (conventional heating) to 180 °C for 1 h, without affecting the formation of perovskite. A 7 wt. % ruthenium-doped SrTiO₃ catalyst showed the best dielectric properties, and thus its catalytic activitywas evaluated for the methane dry reforming reaction under microwave heating in a custom fixed-bed quartz reactor. Microwave power, CH₄:CO₂ feed ratio and the gas hourly space velocity (GHSV) were varied in order to determine the best conditions for performing dry reforming with high reactants conversions and H₂/CO ratio. Stable maximum CH₄ and CO₂ conversions of ~99.5% and ~94%, respectively, at H₂/CO ~0.9 were possible to reach with the 7 wt. % ruthenium-doped SrTiO₃ catalyst exposed to maximum temperatures in the vicinity of 940 °C. The comparative scale-up study showed the significant improvement in terms of H₂ production capability of perovskite catalyst as compared to the carbon-based catalyst.