Effects of Potassium on Carbon Monoxide Methanation Over Supported Rhodium Films

摘要

The reaction of hydrogen with carbon monoxide over Rh/Al2O3 and Rh/TiO2 catalytic films, some of which contained potassium as an additive, has been investigated. The presence of potassium caused the usual gem dicarbonyl and linear CO species on supported rhodium to dissociate at lower temperature than for catalysts containing no potassium. On the other hand, the bridged carbonyl species was significantly enhanced by the presence of potassium. The Rh/TiO2 films to which potassium was added catalyzed the production of significant amounts of acetone and acetaldehyde as oxigenated products. It is likely that the bridged carbonyl species is the precursor to oxygenated products.