Portal de Periódicos da CAPES

Carbon-supported sulfide catalysts

1983; Elsevier BV; Volume: 80; Issue: 2 Linguagem: Inglês

10.1016/0021-9517(83)90263-4

1090-2694

J.C. Duchet, van Em Oers, de Vhj Vincent Beer, R. Prins,

Catalysis and Hydrodesulfurization Studies

The activities of sulfided MoC, WC, CoC, NiC, Co-MoC, and Ni-WC catalysts for thiophene hydrodesulfurization and butene hydrogenation were studied using a flow microreactor operating at atmospheric pressure. The following parameters were varied: type of carbon support, carbon pretreatment, catalyst preparation method, and content of active material. The results are compared with those obtained for series of sulfided Mo/γ-Al2O3, W/γ-Al2O3, MoSiO2, and WSiO2. Some samples, viz., MoC, CoC, and Co-MoC, were also studied by X-ray photoelectron spectroscopy (XPS). The carbon-supported catalysts demonstrated outstanding performance for thiophene hydrodesulfurization. XPS analysis showed the presence of low-valence-state sulfur, e.g., S− or (S-S)2−, in MoC and CoC catalysts with low molybdenum or cobalt content. These sulfurspecies are supposedly connected with the catalytic activity for hydrodesulfurization. CoC and NiC were found to have a hydrodesulfurization activity which was higher (Co) or the same (Ni) as that measured for MoC or WC. Therefore Co (Ni) ions in Co (Ni)-Mo (W)C catalysts are considered as promoters for the MoS2 (WS2) phase (low CoMo or NiW ratios) or as additional active species.