OXIDATION OF METHANOL OVER IRON-OXIDE BASED AEROGELS IN SUPERCRITICALCO2

The oxidation of methanol over iron oxide on silica or molybdenum aero gels using supercritical CO2 as the carrier was investigated for iron oxide content from 1 to 20 wt%. A pure iron oxide aerogel was also pre pared. Partial oxidation products of dimethyl ether, methyl formate, o r formaldehyde were found between 200 to 300 degrees C. Selectivity wa s influenced by the catalyst used. Pure iron oxide favored dimethyl et her, low levels of iron oxide on silica favored methyl formate, and ir on oxide on molybdenum favored formaldehyde. Results demonstrate the f easibility of aerogels as model catalyst systems for reactions in supe rcritical fluids. (C) 1998 Elsevier Science B.V. All rights reserved.