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The influence of calcination temperature on the structure and catalytic behavior of Ni/TiO_2-SiO_2 catalyst,for CO_2 reforming of methane to synthesis gas under atmospheric pressure,was investigated.The results showed that the Ni/TiO_2- SiO_2 catalyst calcined at 700℃had high and stable activity while the catalysts calcined at 550 and 850℃had low and un- stable activity.Depending on the calcination temperature,one,two,or three of the following Ni-containing species,NiO, Ni_(2.44)Ti_(0.72)Si_(0.07)O_4,and NiTiO_3 were identified by combining the temperature programmed reduction (TPR) and X-ray diffraction (XRD) results.Their reducibility decreased in the sequence:NiO>Ni_(2.44)Ti_(0.72)Si_(0.07)O_4>NiTiO_3.It suggests that high and stable activities observed over the Ni/TiO_2-SiO_2 catalyst calcined at 700℃were induced by the formation of Ni_(2.44)Ti_(0.72)Si_(0.07)O_4 and smaller NiO species crystallite size.
The influence of calcination temperature on the structure and catalytic behavior of Ni / TiO_2-SiO_2 catalyst, for CO_2 reforming of methane to synthesis gas under atmospheric pressure, was investigated. The results showed that the Ni / TiO_2-SiO_2 catalyst calcined at 700 ℃ had High and stable activity while the catalysts calcined at 550 and 850 ° C had low and un-stable activity. Delay on the calcination temperature, one, two, or three of the following Ni-containing species, NiO, Ni_ (2.44) Ti_ (0.07) O_4 and NiTiO_3 were identified by combining the temperature programmed reduction (TPR) and X-ray diffraction (XRD) results.Their reducibility decreased in the sequence: NiO> Ni_ (2.44) Ti_ (0.72) Si_ ) O_4> NiTiO_3.It suggests that high and stable activities observed over the Ni / TiO_2-SiO_2 catalyst calcined at 700 ℃ were induced by the formation of Ni_ (2.44) Ti_ (0.72) Si_ (0.07) O_4 and smaller NiO species crystallite size .