Coke-Resistant Ni/CeZrO2 Catalysts for Dry Reforming of Methane to Produce Hydrogen-Rich Syngas.

ABSTRACT

Dry reforming of methane was studied over high-ratio zirconia in ceria-zirconia-mixed oxide-supported Ni catalysts. The catalyst was synthesized using co-precipitation and impregnation methods. The effects of the catalyst support and Ni composition on the physicochemical characteristics and performance of the catalysts were investigated. Characterization of the physicochemical properties was conducted using X-ray diffraction (XRD), N2-physisorption, H2-TPR, and CO2-TPD. The results of the activity and stability evaluations of the synthesized catalysts over a period of 240 min at a temperature of 700 °C, atmospheric pressure, and WHSV of 60,000 mL g−1 h−1 showed that the 10%Ni/CeZrO2 catalyst exhibited the highest catalytic performance, with conversions of CH4 and CO2 up to 74% and 55%, respectively, being reached. The H2/CO ratio in the product was 1.4, which is higher than the stoichiometric ratio of 1, indicating a higher formation of H2. The spent catalysts showed minimal carbon deposition based on the thermo-gravimetry analysis, which was <0.01 gC/gcat, so carbon deposition could be neglected.