Desulfurization Mechanisms on Sulfido Bimetallic Clusters

该奖项将继续支持密歇根大学化学系M.David Curtis博士在脱氢硫化(HDS)催化剂模型络合物反应性方面的研究。该项目的具体目标是确定(1)钼或钨硫化物簇合物的组成、物理和电子结构以及氧化还原性质与其对有机硫化合物的反应性之间的关系；(2)金属簇合物介导的脱硫反应的机理；以及(3)离散簇合物上的脱硫机理如何与石油工业中用于燃料升级的非均相HDS催化剂的脱硫机理有关。实现这些目标的实验方法包括合成新的硫化物双金属簇合物，研究其与有机硫化合物的反应动力学和结构，电化学研究，以及与实际多相催化剂的比较研究。特别令人感兴趣的是那些由铁、钴或镍促进的硫化钼催化剂催化的HDS反应，以及助剂金属在提高催化剂活性方面所起的作用。加氢脱硫(HDS)是一种用于从有机材料中脱除硫的商业过程，因此在制造和改善工业区的空气质量方面非常重要。在本项目中，将制备作为工业催化剂模型的化合物，并考察其反应活性。对助剂在脱硫催化剂中作用机理的了解可用于设计比目前使用的催化剂具有更高活性和选择性的“第二代”加氢处理催化剂。

This award in the Inorganic, Bioinorganic, and Organometallic Program provides continued support for research by Dr. M. David Curtis of the Chemistry Department, University of Michigan, on the reactivity of model complexes for dehydrosulfurization (HDS) catalysts. The specific objectives of the project are to determine (1) how the composition, physical and electronic structure, and redox properties of molybdenum or tungsten sulfide clusters correlate with their reactivity toward organic sulfur compounds; (2) the mechanisms of the desulfurization reactions mediated by the metal cluster complexes; and (3) how the mechanisms of desulfurizations on discrete clusters are related to the mechanisms of desulfurization over the heterogeneous HDS catalysts used in the petroleum industry for fuel upgrading. The experimental approaches to these objectives include the synthesis of new sulfide bimetallic clusters, kinetic and structural studies of their reactions with organic sulfur compounds, electrochemical studies, and comparative studies with actual heterogeneous catalysts. Of particular interest are those HDS reactions catalyzed by molybdenum sulfide catalysts `promoted` with iron, cobalt, or nickel and the role played by the promoter metal in increasing the activity of the catalyst. Hydrodesulfurization (HDS) is a commercial process used to remove sulfur from organic materials and is therefore important in manufacturing and to enhancing air quality in industrial areas. In this project, compounds which are models of the industrial catalyst will be prepared and their reactivity investigated. Knowledge of the mechanistic role of the promoter in desulfurization catalysts can be applied to the design of `second generation` hydrotreating catalysts that possess higher activities and selectivities than those currently in use.