Ruthenium sulphide catalysts supported on alumina: physicochemical characterization and catalytic properties in hydrotreating reactions

Ruthenium sulphide catalysts supported on alumina were prepared using ruthenium III chloride trihydrate and they were sulphided under a N-2/H2S(15%) flow at a number of temperatures. The properties of the catalysts in thiophene hydrodesulphurization, biphenyl hydrogenation and pyridine conversion have been investigated and interpreted in relation to their characterization by X-ray photoelectron spectroscopy, high resolution electron microscopic observations and temperature-programmed reduction data. The results show the importance of the sulphidation step in the genesis of different active RuS2 particles. The relation between the activity and the nature of the exposed crystallographic planes is discussed.