Sulfur uptake determination on Ni containing molybdena-alumina samples by radioisotope tracer technique

Five solid oxides, used as hydrodesulfurization catalysts (Al2O3 supported Ni, MoOx, Ni–MoOx-s of different Ni:Mo ratio) were sulfided by [35S]H2S. Amounts of the total, reversible and irreversible sulfur uptakes were determined measuring the change of gas phase radioactivity during exposure [35S]H2S to the oxides, and compared with the amounts determined measuring radioactivity of the sulfided samples. The S/(Ni+Mo) values determined by X-ray photoelectron spectroscopy (XPS) were in satisfactory agreement with the results obtained by radiosulfur. Significantly different sulfur uptakes were observed for the different samples.