Novel type of carbon-supported catalysts. I.Preparation and characterization

The exposure of CoO/Al2O3 catalysts to carbon monoxide leads, after reduction to cobalt metal, to the formation of filamentary carbon in addition to a less reactive form of deposited carbon. The filament diameters were determined by scanning electron microscopy. The carbon content was determined by temperature-programmed oxidation. The carbon filament diameter increased with increasing exposure temperature, whereas the total carbon deposition decreased at higher temperatures. CoO-MoO3/Al2O3 catalysts exposed to carbon monoxide also showed carbon deposition, but no filaments were formed, so carbon deposition on these catalysts took place via a different route. The filament-containing catalysts are referred to as tulip-field catalysts