Structural and surface features of PtNi catalysts for reforming of methane with CO2

The effect of Ni content (1-12 wt%) on the surface and catalytic behavior of bimetallic PtNi catalysts supported on ZSM-5 for reforming of. methane with CO2 was studied. The properties of the catalysts, before and after exposure to reaction conditions, were investigated employing NZ adsorption-desorption isotherms, XRD, TGA/DTA, FTIR spectroscopy of framework vibrations, DRIFT spectroscopy of adsorbed CO, XPS and TPR. It was shown that addition of a small amount of Pt (0.5%) to Ni catalyst leads to formation of small nano-sized NiO particles and easy reduction of NiO. It was found that the amount of Ni precursor plays an important role on the surface and catalytic properties of bimetallic catalysts. The improvement of catalytic activity and stability observed for bimetallic catalyst was attributed to an increase of the nickel metallic dispersion caused by an intimate contact between nickel and platinum at Ni-loading of 6 wt%. (C) 2007 Elsevier B.V. All rights reserved.