REACTIVITY AND MORPHOLOGY OF Ni, Mo, AND Ni–Mo OXIDE CLUSTERS SUPPORTED ON MCM-48 TOWARD THIOPHENE HYDRODESULPHURIZATION CATHERINE BARTHOLOMEW, ASHISH CHAKRADHAR and UWE BURGHAUS * Department of Chemistry and Biochemistry, North Dakota State University, Fargo 58108, USA * Uwe.Burghaus@ndsu.edu CHIA-MING WU † , RUI PENG † , SRUJAN MISHRA ‡ and RANJIT T. KOODALI †,§ † Department of Chemistry, University of South Dakota, Vermillion 57069, USA ‡ Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, Rapid City 57701, USA § Ranjit.Koodali@usd.edu Received 4 April 2014 Revised 13 May 2014 Accepted 17 June 2014 Published 9 July 2014 In this paper, the morphology, chemical composition and reactivity of MCM-48 powders impreg- nated with Ni, Mo or both toward hydrodesulphurization (HDS) of thiophene were characterized. The reactivity of the catalyst was quantitatively compared with a standard industrial catalyst (from HaldorTopsoe, Denmark) and a novel WS 2 nanotube-based catalysts (from R. Tenne, Israel). Morphology and chemical composition were characterized by transmission electron microscopy (TEM), X-ray di®raction (XRD), energy dispersive X-ray spectroscopy (EDX), and EDX elemental maps. Reactivity was determined in a gas-chromatograph based mini °ow reactor using thiophene as a probe molecule. The sul¯ded MCM-48 supported Mo catalyst showed the largest HDS activity with turnover frequencies (TOF) about half as large as for the commercial system under the test conditions used here. Presul¯ding did increase activity of all MCM-48 catalysts. Keywords: Microporous materials; nanostructures; catalytic properties; surface properties; chemical synthesis. 1. Introduction In the industrial hydrodesulfurization (HDS) process, sulfur-containing species are treated with hydrogen by catalysts to obtain sulfur-free hydrocarbons. We are aware of about two dozen reviews starting in the 1950s. Many of these focused on industrial systems at high-pressure conditions, and a few are explicitly cited here (see Refs. 1–15). In model studies, thiophene (C 4 H 4 S) is the probe molecule of choice since thiophene is part of natural petroleum and it may be a simple Surface Review and Letters, Vol. 21, No. 5 (2014) 1450060 (11 pages) ° c World Scienti¯c Publishing Company DOI: 10.1142/S0218625X14500607 1450060-1 Surf. Rev. Lett. Downloaded from www.worldscientific.com by Professor Ranjit Koodali on 08/06/14. For personal use only.