TY - JOUR
T1 - Platinum–Rhenium synergy on reducible oxide supports in aqueous-phase glycerol reforming
AU - Ciftci, A.
AU - Eren, S.
AU - Ligthart, D.A.J.M.
AU - Hensen, E.J.M.
PY - 2014
Y1 - 2014
N2 - A significant support effect was observed for the aqueous-phase reforming (APR) of glycerol over a series of Pt- and PtRe-loaded ceria-, ceria–zirconia-, zirconia-, and titania-supported catalysts. Glycerol conversion rates decreased in the order Pt/TiO2>Pt/ZrO2>Pt/CeZrO2>Pt/CeO2. Upon addition of Re, APR activities of all the Pt catalysts increased. Re promotion for glycerol APR was strongest for PtRe/CeO2. Pt/CeO2 was least active because of the incomplete reduction of Pt. Pt was more easily reduced in PtRe/CeO2 because of the strong Pt–Re interaction. On comparison with previous data on Pt/C and PtRe/C, the oxide-supported catalysts were more active in the WGS reaction, with the titania-supported catalyst as the most active, which was a result of the activation of water on the titania support. The acidity of these groups also resulted in increased CO cleavage rates of Pt/TiO2 relative to the rates of Pt/C in APR. A more detailed comparison of Pt(Re)/C and Pt(Re)/TiO2 is made. Monitoring acetaldehyde decomposition to determine the rate of CC bond cleavage evidenced a strong promoting effect of Re on the supported Pt catalysts. All catalysts produced carbon monoxide, methane, and ethanol during acetaldehyde decomposition; notably, Pt(Re)/TiO2 also formed products such as ethylene, ethane, propylene, and propane, indicative of a mechanism also involving ethanol dehydration and olefin coupling to CHx surface intermediates derived from acetaldehyde. The activity in overall glycerol conversion in APR decreased in the order PtRe/C>PtRe/TiO2>Pt/TiO2>Pt/C.
AB - A significant support effect was observed for the aqueous-phase reforming (APR) of glycerol over a series of Pt- and PtRe-loaded ceria-, ceria–zirconia-, zirconia-, and titania-supported catalysts. Glycerol conversion rates decreased in the order Pt/TiO2>Pt/ZrO2>Pt/CeZrO2>Pt/CeO2. Upon addition of Re, APR activities of all the Pt catalysts increased. Re promotion for glycerol APR was strongest for PtRe/CeO2. Pt/CeO2 was least active because of the incomplete reduction of Pt. Pt was more easily reduced in PtRe/CeO2 because of the strong Pt–Re interaction. On comparison with previous data on Pt/C and PtRe/C, the oxide-supported catalysts were more active in the WGS reaction, with the titania-supported catalyst as the most active, which was a result of the activation of water on the titania support. The acidity of these groups also resulted in increased CO cleavage rates of Pt/TiO2 relative to the rates of Pt/C in APR. A more detailed comparison of Pt(Re)/C and Pt(Re)/TiO2 is made. Monitoring acetaldehyde decomposition to determine the rate of CC bond cleavage evidenced a strong promoting effect of Re on the supported Pt catalysts. All catalysts produced carbon monoxide, methane, and ethanol during acetaldehyde decomposition; notably, Pt(Re)/TiO2 also formed products such as ethylene, ethane, propylene, and propane, indicative of a mechanism also involving ethanol dehydration and olefin coupling to CHx surface intermediates derived from acetaldehyde. The activity in overall glycerol conversion in APR decreased in the order PtRe/C>PtRe/TiO2>Pt/TiO2>Pt/C.
U2 - 10.1002/cctc.201301096
DO - 10.1002/cctc.201301096
M3 - Article
SN - 1867-3880
VL - 6
SP - 1260
EP - 1269
JO - ChemCatChem
JF - ChemCatChem
IS - 5
ER -