(765e) Low Temperature Dry Reforming of Methane over Pt Promoted NiCe@SiO2 Multi–Yolk–Shell Nanotube Catalysts
In this work, Pt promoted NiCe@SiO2 multiâyolkâshell nanotube catalysts have been investigated for low temperature (500 ÂºC) DRM. Our previous results confirmed that the NiCe@SiO2 multiâyolkâshell nanotube structure could exhibit a high turnover frequency and high resistance to carbon deposition compared to conventional NiCe/SiO2Imp synthesized by impregnation method in tri-reforming of methane at 750 ÂºC. These multiâyolkâshell nanotube structures have been further evaluated for DRM reaction at 500 ÂºC and the effect of Pt promotion is investigated. Our results indicated that NiCe@SiO2 without Pt promotion shows initial CO2 and CH4 conversions of 12.1% and 6.7%, respectively, which are lower than the CO2 (16.8%) and CH4 (11.6%) conversions on conventional NiCe/SiO2Imp. However, the activity of Pt-NiCe@SiO2 with 1 wt.% of Pt promotion increases CO2 and CH4 conversions to 17.3% and 11.7%, respectively. The Pt-NiCe@SiO2 shows stable activity, whereas the activity of Pt-NiCe/SiO2Imp decrease to 48.7% of its initial activity during 20 h of DRM reaction. On the other hand, Pt-NiCe@SiO2 with 0.25 wt.% of Pt promotion has higher resistance to carbon deposition than any other catalysts in our work. It is possible that the PtâNi alloy formation and multiâyolkâshell nanotube structure could enhance the DRM activity and lead to a lower carbon deposition. In the presentation, we will provide a detailed characterization of the samples using electron microscopy and x-ray spectroscopy, and elucidate the effect of Pt and Ni interaction on catalyst activity.