Studies on nickel-based catalysts for carbon dioxide reforming of methane

摘要

The catalytic activity and coke resistance of La_2O_3 promoted nickel-based catalysts are investigated in a fixed-bed flow reactor.The contents of carbon deposited on catalysts were measured by a carbon combustion method.Catalysts were characterized by CO-TPD,CO_2-TPD,TPR,XPS and XRD techniques,and the results were correlated with the coke resistance of the catalysts.It is found that the catalytic activity,resistance to carbon deposition and the stability of the catalysts can be greatly improved with the addition of a rare earth oxide.It is found that BaTiO_3 is an ideal support.Thus 5.0 wt.% Ni-0.75 wt.% La-BaTiO_3 catalyst shows great resistance to coke formation and higher thermal stability as well as higher catalytic activity,than the catalysts 5.0 wt.% Ni/La-BaTiO_3(Ba/La=1/0.002)and 5.0 wt.% Ni-1.5 wt.% La/BaTiO_3.