Journal of Chemical Technology and Biotechnology, Vol.59, No.2, 181-191, 1994
MoO3-Fe2O3 Catalysts - Characterization and Activity for Isopropyl-Alcohol Decomposition
The vapour-phase dehydration and dehydrogenation of isopropyl alcohol (IPA) have been carried out over pure MoO3 and Fe2O3, produced by calcination of ammonium heptamolybdate and of iron (III) nitrate respectively, as well as MoO3 mixed with 0.5 and 50 mol % Fe2O3, Prepared from the same materials. All catalysts were calcined in air, in the temperature range 200-600-degrees-C for 5 h, and were characterized by thermal analysis (TG, DTA), XRD, IR and S(BET). Surface areas decreased with increasing calcination temperature, and the catalytic activity of the pure oxides MoO3 and Fe2O3, as well as Of MoO3-0.5 mol % Fe2O3, increased with their S(BET). The activity Of MoO3-50 mol % Fe2O3, which was independent of its S(BET), could be attributed to the increased intensity of terminal Mo-O bonds as shown by IR spectra. The activation energies for the decomposition of IPA over catalysts calcined at 250 and 500-degrees-C are tabulated.
Keywords:ACID-BASE PROPERTIES;SELECTIVE OXIDATION;METHANOL OXIDATION;FERRIC MOLYBDATE;OXIDE CATALYSTS;FE2(MOO4)3;PROPYLENE;BI