Dry reforming of methane over ZrO2-supported Co-Mo carbide catalyst

The process of dry reforming of methane has the potential to be an effective route for CO2 utilization via syn-gas production. In the present study, ZrO2-supported Co-Mo bimetallic carbide catalysts were prepared via a coprecipitation method through a combined reduction and carburization procedure employing a CH4/H-2 (20/80 %) mixture. All of the as-synthesized materials were tested at 850 degrees, under atmospheric pressure and a CO2: CH4 ratio of 1. The importance of the ZrO2 support became immediately apparent when it exhibited a higher conversion than the corresponding low-surface-area bulk Mo2C catalyst, which we attribute to lewis acid and base active sites on the surface of ZrO2. From catalytic tests and pre-and postreaction X-ray diffraction (XRD) patterns, we observed that different dispersions of the monometallic carbides, caused by varying the pre-heating temperatures on ZrO2, did not significantly affect conversion or yield. In contrast, incorporation of cobalt atoms into the Mo2C lattice significantly enhanced the conversion, yield and stability of the catalysts. Post-reaction XRD patterns indicated that the bimetallic carbide had enhanced the resistance to the oxidation effect that is known to deactivate Mo2C catalysts. In addition, increasing the Co loading in the mixed metal carbides was seen to enhance the resistance of the catalyst to the reverse water gas shift reaction, leading to improved stability of the H-2 yields.