MO/AL2O3 CATALYSTS PREPARED VIA METAL-COMPLEX PRECURSORS .2. SORPTION OF METAL-COMPLEXES BY THE SUPPORT SURFACE

The interaction of metal complexes MoO2(C5H7O2)2, (N2H5)2[Mo2O4(C2O4)2(H2O)2], and (NH4)2[Mo3O4(C2O4)3(H2O)3] with the surface of γ-Al2O3 was studied by NMR spectroscopy on the nuclei 95Mo, 27Al, 17O, 14N, and 13C, while the composition of surface species formed was studied by IR spectroscopy. The interaction between molybdenum acetylacetonate and the support surface occurs according to the mechanism of ligand substitution, whereas the sorption of oxalate complexes of Mo is shown to occur according to both the mechanism of ligand substitution and the mechanism of ion exchange. In all cases aluminum complexes having the respective chelate ligands have been found in the mother solution. © 1993 Academic Press, Inc.