New approaches to improving catalyst stability over Pt/ceria during ethanol steam reforming: Sn addition and CO sub(2) co-feeding

• Published in: Applied catalysis. B, Environmental Environmental, 2010-06, Vol.96 (3-4), p.387-398
• Main Authors: De Lima, Sania M, Da Silva, Adriana M, Jacobs, Gary, Davis, Burtron H, Mattos, Lisiane V, Noronha, Fabio B
• Format: Article
• Language: English
• ISSN: 0926-3373
• DOI: 10.1016/j.apcatb.2010.02.036

To promote long-term stability of Pt/CeO sub(2) catalyst for ethanol steam reforming, two approaches were examined. Sn was added to Pt to suppress carbon formation. Although the catalyst with high Sn content exhibited improved stability, acetaldehyde selectivity was prohibitive. DRIFTS experiments revealed that Sn inhibited the ability of Pt to facilitate steam-assisted forward acetate decomposition reaction to carbonate, the precursor to CO sub(2) formation. However, CO sub(2) co-feeding was more effective, not only in promoting long-term catalyst stability, but also in maintaining high H sub(2) selectivity. DRIFTS experiments indicate that the kinetic influence of CO sub(2) can be explained as a competition with ethanol for adsorption sites, leading to a suppression in the rate of formation of coke precursors.