NOVEL NANO-SCALE Au/α-Fe2O3 CATALYST FOR THE PREFERENTIAL OXIDATION OF CO IN BIOFUEL REFORMATE GAS

Au/alpha-Fe2O3 catalyst was synthesized using a modified co-precipitation method to generate an inverse catalyst model. The effects of introducing CO2 and H2O during preferential oxidation (PROX) of CO were investigated. The goal of this work was >= 99.8% CO conversion at 80 degrees C. There was an increase in the conversion at all temperatures with the introduction of CO2 and 100% of the CO was converted at the target temperature of 80 degrees C for any amount of CO2. Furthermore, there was an increase in conversion to 100% for water fractions ranging from 3% to 10%. Finally, for realistic conditions of (bio-)fuel reforming, 24% CO2 and 10% water, 99.85% conversion was achieved. A long-term test of 200 hours showed no significant deactivation of the catalyst at a temperature of 80 degrees C in presence of 24% CO2 and 3% water. The mechanism for PROX is not known definitively, however, current literature believes the gold particle size is the key. In contrast, we emphasize the tremendous role of the support particle size.