Monoliths washcoated with AuCu catalysts for CO removal in an ethanol fuel processor: Effect of CeO2–SiO2 dual support on the catalytic performance and reactor cost

Abstract CO removal from a syngas was evaluated in a single catalytic unit using structured AuCu/CeO2–SiO2 catalysts. Initially, AuCu/CeO2–SiO2 powder catalysts with several SiO2 loadings (0–100 mol%) were assessed. SiO2 addition into AuCu/CeO2 increased the surface area by up to 3.4 times and reduced its cost by up to 60%, but reduced CO conversion. On the other hand, the AuCu/CeO2–SiO2 catalyst washcoated on monolith outperformed the powder samples at temperatures above 260 °C. In particular, outlet CO concentrations adequate to feed high temperature fuel cells were obtained with monoliths washcoated with AuCu/CeO2 (0.2% CO) and AuCu/CeO2–SiO2 with 75 mol% of SiO2 (3.6% CO). Furthermore, the Au/CeO2–SiO2 monolith (14 $/gcat) is 36% cheaper than the AuCu/CeO2 monolith, paving the road to the development of compact and economic H2 cleanup processes.