Simultaneous hydrodesulfurization of thiophene and hydrogenation of cyclohexene over dimolybdenum nitride catalysts

A series of unsupported dimolybdenum nitride (gamma-Mo2N) catalysts differi ng in surface area were prepared by temperature programmed reduction of MoO 3 with a mixture of NH3:N-2 (90:10). Characterization of catalysts by BET, XRD, TPR and XPS techniques was carried out. The samples were used as catal ysts in hydrotreating reactions (simultaneous hydrodesulfurization of thiop hene and hydrogenation of cyclohexene). Low surface area gamma-Mo2N materia ls show much higher specific conversions than those with higher surface are a. These results indicate that HDS and HYD reactions over gamma-Mo2N seem t o be structure-sensitive. The relative exposure extent of crystalline plane s (111) and (200) over the different catalysts can be associated with their hydrogen adsorption capacities and with their catalytic performances. The catalytic activities are significantly affected by the catalyst pretreatmen t conditions. (C) 1999 Elsevier Science B.V. All rights reserved.