Influence of the Precursor on Cerium Distribution over Alumina

The Ce/Al2O3 catalysts were prepared with Ce(NO3)3, (NH4)2Ce(NO3)6 and with cerium acethylacetonate precursors over alumina, by impregnation and grafting, respectively. Results have shown that the CeO2 surface area of the catalysts with the nitrate precursors is very similar but much higher on the catalysts with the acethylacetonate after grafting. The reducibility of this catalyst is better than of the catalysts with the nitrate precursor. TPR results indicate a reduction of CeO2, the formation of CeAlO3 and Ce2O3. The experimental condition employed here allows to attain saturation over alumina which is probably due to steric effects of the Ce(Acet)3 molecules.