SURFACE-FEATURES AND CATALYTIC PERFORMANCE OF PLATINUM ALUMINA CATALYSTS IN SLURRY-PHASE HYDROGENATION

Several platinum catalysts supported on three commercial gamma-alumina s were prepared by impregnation and anionic exchange using aqueous sol utions of H2PtCl6. A number of methods were used to characterize the p recursors as well as the final catalysts, including TGA, TPR, and hydr ogen chemisorption at 298 K. TPR measurements showed two reduction pea ks for the catalysts: the first one corresponding to reduction of the metal precursor to platinum and the second one associated to formation of a surface complex, Pt-Al2O3-x, with partial reduction of the suppo rt. The activity of the different catalysts was tested in the slurry-p hase hydrogenation of benzene. The results obtained in the activity me asurements have been correlated to the characteristics of the catalyst s.