GAS-PHASE DEPOSITION AND THERMAL TRANSFORMATIONS OF CR(ACAC)(3) ON THE SURFACE OF ALUMINA SUPPORTS

Gas-phase deposition and subsequent thermal activation of Cr(acac)(3) on the surface of fumed and precipitated alumina supports have been st udied by diffuse reflectance FTIR spectroscopy, TG-DTG, TPO and chemic al analysis. It has been found that stabilisation of Cr(acac)(3) on al umina occurs in a molecular form owing to the donor-acceptor interacti on of the acetylacetonate ligands with surface hydroxy groups and coor dinatively unsaturated Al3+ ions. Thermally activated processes of rem oval of acetylacetonate ligands assisted by proton transfer and acetyl acetonate ligand pyrolysis have been discriminated.