Abstract
The CO(2) methanation reaction of reduced and unreduced Ni based CeO(2), Al(2)O(3), TiO(2) and Y(2)O(3) supported catalysts was investigated. The Ni/CeO(2) and Ni/Y(2)O(3) catalysts exhibited similar CO(2) conversions at all reaction temperatures. The catalysts were studied by X-ray diffraction (XRD), H(2) chemisorption, H(2) temperature-programmed reduction (TPR), and in situ diffuse reflection infrared Fourier transform spectroscopy (DRIFTS); the results suggested that the reducibility of both metal and support at low temperature, strong metal support interaction and small Ni particle size are important factors for low-temperature CO(2) methanation. Based on the DRIFT studies, the difference in the CO(2) adsorption properties and reaction pathway depending on the reduced and unreduced Ni based supported catalysts was discussed.