Segregation of Pt and Re During CO2 Reforming of CH4

Abstract

Pt-Re supported on Ce 0.52 Zr 0.48 O 2 was studied for the carbon dioxide reforming of methane at 800°C. Diffuse reflectance fourier transform infrared spectroscopy and temperature programmed reduction studies suggest that Pt and Re segregation occurs during the reaction. The segregation results in an increase in the Pt sites available for CH 4 decomposition and results in the bimetallic catalyst exhibiting an increase in the conversion of methane with time on stream. After 20 h of reaction, the CH 4 conversion observed for the bimetallic catalyst was the same as the CH 4 conversion observed for the monometallic catalyst.

Review of Pt-Based Bimetallic Catalysis: From Model Surfaces to Supported Catalysts

“…323 In addition to the metal affecting selectivity, the support has been found to play a major role in Pt−Sn catalysts. A carbon nanotube (CNT) support can be useful to concentrate reactants in an area close to the active metal, 300 whereas supports that exchange oxygen with the reactants, such as TiO 2 , 297 ZnO, 324 or CeO 2 , 324 have been shown to dramatically affect reaction chemistry. The addition of Sn to a Pt catalyst on a reducible support can influence the ability of the support to remove surface carbon through oxygen exchange 324 and help to maintain Sn in a fully reduced state.…”

“…A carbon nanotube (CNT) support can be useful to concentrate reactants in an area close to the active metal, whereas supports that exchange oxygen with the reactants, such as TiO 2 , ZnO, or CeO 2 , have been shown to dramatically affect reaction chemistry. The addition of Sn to a Pt catalyst on a reducible support can influence the ability of the support to remove surface carbon through oxygen exchange and help to maintain Sn in a fully reduced state . The removal of surface carbon is critical to prevent deactivation of the catalyst.…”