(10c) Catalytic Performance and Stability of MIL-47 and MIL-125 in Oxidative Desulfurization Reactions

The desire to obtain cleaner fossil fuels from petroleum feedstocks has led to increasingly restrictive limits on the sulfur content in fuels.  The selective removal of these heterocyclic aromatic sulfur contaminants in fuel streams is possible through the discovery and investigation of new, selective catalysts.  Metal-organic frameworks (MOFs) are an important class of materials that are comprised of metal nodes and organic ligand connectors that form crystalline, porous materials.  MOFs are useful in many areas including gas separations, gas storage, and catalysis.[1,2]  In this presentation, we will discuss our recent results using Ti- and V-based MOFs.[3]  Specifically, MIL-125 (Ti) and MIL-47 (V) were synthesized and characterized using transmission electron microscopy (TEM), x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), FT-IR spectroscopy, Raman, thermogravimetric analysis (TGA), and N₂ physisorption to confirm their structure and chemical composition.   Both MOFs were subsequently tested for their catalytic activity in the oxidation of dibenzothiophene, benzothiophene, and thiophene.  Additionally, detailed reaction studies coupled with TEM and XRD analyses were performed to determine the stability of these MOFs after oxidation reactions.

[1]    Corma, A.; Garcia, H.; Xamena, F. X. L., Chem Rev 2010, 110, 4606-4655.

[2]    Dhakshinamoorthy, A.; Alvaro, M.; Garcia, H., Catal Sci Technol 2011, 1, 856-867.

[3]    McNamara, N.D; Neumann, G.T.; Masko, E.T.; Urban, J.A.; Hicks, J.C., J. Catal.,       2013, in revision.