Carbon dioxide reforming of methane over zirconia promoted Ni-based double-layered hydroxides

A series of zirconia promoted Ni-based hydrotalcite (HTZr) were prepared via co-precipitation method and evaluated in CO2 reforming of methane. It was found that Zr can be successfully introduced into the structure of hydrotalcite. BET, XRD, H-2-TPR, CO2-TPD, TG and TEM were conducted to describe the physicochemical properties of the HTZr samples. The incorporation of Zr promoted the basicity of catalysts, which favors the elimination of carbon deposition during CO2 reforming of methane. HTZr2 (Zr/Al = 0.06) exhibited high CH4 conversion and extreme stability for CO2 reforming of methane within 36 h of reaction at 650 degrees C and 48 000 mL/(g h), due to the high dispersion of Ni and the enhanced basicity. In addition, the results of H-2-TPR showed that the incorporation of moderate amounts of Zr promoted the reducibility of Ni. However, the high loading of Zr slightly destroyed the structure of the hydrotalcite and resulted in the aggregation of Ni particles. Furthermore, the incorporation of Zr changed the morphology of carbon species, facilitated the formation of carbon nano-tubes.