随着环境问题的日益严峻，汽柴油深度脱硫的重要性凸显。加氢脱硫方法面临的共性催化技术难题是难以脱除二苯并噻吩（DBT）类含硫化合物，特别是有烷基取代的衍生物，如4,6-二甲基二苯并噻吩（4,6-DMDBT）。4,6-DMDBT类含硫化合物的低活性与其骨架分子为平面结构有关， 4位和6位的甲基取代基对S原子接近表面活性中心会产生更大的空间位阻。因此，要有效脱除4,6-DMDBT类含硫化合物需要使其芳环加氢饱和，从而消减空间位阻并消除共轭效应。我们最近发现MoP和WP上4,6-DMDBT的加氢脱硫活性高于位阻小的DBT，通过探针反应证实它们在反应条件下具有很高的芳环加氢饱和活性。本项目计划深入研究MoP和WP的结构与其特异加氢性能的关系，揭示加氢脱硫反应路径、反应动力学网络和催化反应机理，通过改性和与传统催化剂组合构建高效深度加氢脱硫催化体系，为高性能催化剂的设计、开发和应用提供科学和技术支撑。

Altra-deep desulfurization of petroleum and diesel fuels are of great importance due to severe environmental issues. Hydrodesulfurization(HDS) process is limited in treating dibenzothiophene(DBT) derivatives, especially DBTs having alkyl substituents (e.g. 4,6-dimethyldibenzothiophene (4,6-DMDBT)). Such polyaromatic sulfur molecules are very difficult to convert due to its steric-hindrance remarkably retards the rate of HDS even under deep desulfurization conditions. Therefore, the effective strategy to treat 4,6-DMDBT is to saturate its aromatic ring, thus to reduce steric-hindrance and eliminate conjugative effects. We have recently found that 4,6-DMDBT have shown higher HDS activity over MoP and WP catalysts than that of DBT. Probe reactions confirmed that such catalysts have remarkable hydrogenation activity to saturate aromatic ring. In this project we will take this research one step further. The relationship between MoP and WP structure with their specific hydrogenation performance will be investigated, the catalytic reaction mechanism will be proposed. Our final goal is to establish a highly efficient catalytic system for altra-deep hydrodesulfurization, which will give future guidance for the design and development of high-performance hydrodesulfurization catalyst.