Hydrodesulfurization of dibenzothiophene and hydrogenation of phenanthrene on alumina-supported Pt and Pd catalysts Original Research Article

Hydrodesulfurization (HDS) reactions of dibenzothiophene (DBT) and hydrogenation (HYD) of phenanthrene (PHE) were carried out over several alumina-supported noble metal catalysts at temperatures between 200°C and 400°C and under 50 kg/cm2 pressure. A dual noble metal catalyst, Pt(2)–Pd(10), showed similar HDS results and better HYD promotion compared with a conventional Co–Mo catalyst. Further, 35S radioisotope tracer method showed that almost no labile sulfur was accumulated on Pt/Al2O3 catalyst in the HDS of DBT or HYD of PHE, although this catalyst showed an HDS activity comparable to that of the Co–Mo catalyst. This indicated that the mechanism of DBT HDS on noble catalysts was different from that on the conventional Mo-based catalyst.