AIR GASIFICATION OF ACTIVATED CARBONS AND CHARS CATALYZED BY CR2O3 AND MOO2

A study was made of the gasification in air of activated carbons and coal chars, using Cr2O3 and MoO2 catalysts. The activated carbons were prepared from olive stones and had different surface areas and porosities. The rank of the parent coals used ranged from anthracite to lignite. Cr and Mo were deposited on these samples from chromium nitrate, ammonium chromate and ammonium hepta-molybdate, using water or ethanol as the solvent. The samples were characterized by physical adsorption of CO2 at 298 K, X-ray diffraction, transmission electron microscopy (of selected samples) and oxygen chemisorption at 553 K. The oxygen uptake at that temperature was taken as a measure of the number of active surface sites present on the metal oxide. Reactivity of the samples at 733 K in dry air was measured by a thermogravimetric method, and the reactivity was related to oxygen uptake by the metal oxides at 553 K. © 1990.