Zirconium-substituted Hexaaluminates La_(0.8)Zr_xNiAl_(11)O_(19-δ) for Carbon Dioxide Reforming of Methane

摘要

A study on zirconium-modified hexaaluminates La_(0.8)Zr_xNiAl_(11)O_(19-δ) (x= 0, 0.02, 0.04, 0.06, 0.08, and 0.10) for CO2 reforming of CH4 was carried out. The modifier zirconium improved the catalytic activity, especially the conversions of CH4 and CO2 reached 93.4% and 97.7% over La_(0.8)Zr_xNiAl_(11)O_(19-δ) . Both the XPS and TPR data indicated the presence of Ni~(3+) and Ni~(2+). It was found that the Ni~(3+) and Ni~(2+) ratio depended upon the amount of the Zr, which facilitated the formation of highly dispersed active Ni° species.