INFRARED SPECTRA OF CARBON MONOXIDE AND CARBON DIOXIDE ADSORBED ON CHROMIA–ALUMINA AND ON ALUMINA

Abstract

Infrared spectra of CO and CO₂ adsorbed on chromia–alumina and on alumina surfaces have been determined. A band near 2200 cm−¹ formed by CO on both surfaces at room temperature was due to a weak, non-activated sorption, but also contained a contribution from a more strongly sorbed, activated species on the chromia–alumina. The assignment of this band was discussed in some detail. Bands in the region 1200–1800 cm−¹ were considered in terms of surface CO₂− species, although in certain instances the appearance of bands at 1750 and 1430 cm−¹ may have indicated carbonate ion formation.