Hexamethylenetetramine-assisted hydrothermal synthesis of efficient and stable Ni-MoCeZr-MgAl(O) catalysts for dry reforming of CH_4: Effect of Ni content

摘要

Ni-MoCeZr-MgAl(O) mixed oxide catalysts were successfully prepared from the Ce, Zr and Mo promoted hydrotalcite-like compounds (HTLcs) precursors using the simple and effective hexamethylenetetramine(HMT)-assisted hydrothermal synthesis method by tuning the molar ratio of n(HMT)(NO3 (-)). The influence of Ni content (3, 4.8, 6, 9 and 12%) on the catalytic performance of these catalysts in dry reforming of methane (DRM) was focused. Adjusting the content of Ni was able to change the metal dispersion and metal particle size, and small-sized (around 7 nm) and evenly dispersed Ni particles were obtained at Ni content of 6%. The catalyst with 6% Ni loading stood out for the high activity and stability, the CH4 conversion of which fluctuated around 95% continuously for 610 h under GHSV of 60,000 mL.g(cat)(-1).h(-1), and it was still above 92.8% throughout the 36-hduration DRM experiments under GHSV of 80,000 mL.g(cat)(-1).h(-1). This research may provide a simple and effective methodology for the synthesis of stable and efficient DRM catalysts.