This Small Business Innovation Research (SBIR) Phase I project is in the general area of analytical and surface chemistry and in the subfield of heterogeneous catalysis. The thrust of this activity focusses on fundamental investigations of metal sulfide cluster-oxide support systems for hydrodesulfurization (HDS). Hydrodesulfurization remains a poorly understood reaction despite very extensive study. The use of cluster-derived catalysts for HDS represents a novel approach to identifying the active site for HDS and understanding its physicochemical nature. This type of catalyst could also have improved activity and selectivity relative to conventionally prepared HDS catalysts. In the execution of the research plan of this project, Dr. Thompson will investigate the behavior of the homonuclear sulfide clusters Cp2Mo2(uS)2(uSH)2, Fe2(uS)2(CO)6,and Co6(u3S)2(CO)12. Because these clusters contain bridging sulfide ligands, their metal frameworks are expected to be very robust and stable under HDS reaction conditions. These clusters will be synthesized and supported on partially dehydroxylated gamma-Al2O3 and MgO. The pure and supported catalysts will be characterized by a variety of analytical techniques including infrared spectroscopy, surface area analysis, X-ray diffraction, and X-ray photoelectron spectroscopy. Mechanistic insights into the HDS reaction garnered from these studies will be used as the basis for a model of this important catalytic process.
