新型Beta基介微孔材料催化剂的定向合成及柴油超深度脱硫反应机理研究

Stringent regulation of environmental protection impels the production of ultra clean diesel. The core of technical upgrading of hydrotreating is the development of novel catalyst. This proposal focuses on the directional synthesis of novel Beta-based hierarchically meso-microporous structure material of Beta-KIT-6 with suitable acidity and tunnel arrays. Based on the typical characteristics of molecular sizes and configurations of sulfides existed in diesel these novel composites combine the structure and acidity superiorities of mesoporous KIT-6 and microporous Beta zeolites. Through the optimization and the directional synthesis of pore structures and acid properties, a kind of novel catalyst with high activity and selectivity will be prepared to meet the production demands of ultra clean diesel. Simultaneously, this research will systematically study the diffusion properties of model sulfide molecules with different sizes and structures over the above novel hierarchically porous materials by adopting kinetics diffusion model. Combined with the characterization results of different analytical technologies, the structure-activity-relationship between these novel catalysts and their performance will be discussed in detail. The hydrodesulfurization mechanisms of reactant molecules over these novel catalysts will be studied carefully by integrating the analytical informations of intermediate and final products with special methods of GC-PFPD, In-situ IR and Raman, etc. This proposal of project will be significant to the theoretical research of hydrodesulfurization and to the practical production of ultra clean diesel by incorporating the in-situ synthesis of novel materials and their corresponding catalytic performances related to the catalyst structures and acidity properties.

日益严格的环保法规极大推动了超清洁油品的生产进程。新型高活性超深度加氢脱硫催化剂的研发是技术升级的关键。本研究针对柴油中难脱除硫化物分子尺寸大、存在烷基位阻的特点，定向设计合成酸性适宜、具有三维介微孔梯级孔道结构的Beta-KIT-6复合材料，集介孔材料KIT-6的孔道优势与微孔分子筛Beta的适宜酸性于一体，通过优化调变催化剂孔道结构、酸性及理化性质实现催化剂高HDS活性，为应对超清洁油品生产需求提供性质优良、可定向调控的优质催化剂。同时，采用动力学扩散模型，系统研究不同尺度和结构的模型硫化物分子在梯级孔道材料中的扩散规律；结合催化剂表征结果，探讨催化剂反应活性与其结构性质及扩散性能之间的构效关系。通过加氢反应中间及最终产物分析，结合GC-PFPD、In-situ IR、Raman等方法细致研究复合孔道材料上加氢深度脱硫反应机理和规律，对实现国V标准清洁柴油生产具有重要的理论和应用意义。

超清洁柴油的生产和使用对保护环境具有深远重要意义。新型高活性超深度加氢脱硫催化剂的研发是加氢技术升级换代的关键。本研究针对柴油中难脱除硫化物分子尺寸大、存在烷基位阻的特点，定向设计合成酸性适宜、具有三维介微孔梯级孔道结构的Beta-KIT-6(BK)复合材料，通过优化调变催化剂孔道结构、酸性及理化性质实现高催化HDS活性。同时，通过加氢反应中间及最终产物的分析，结合GC-PFPD等方法细致研究复合孔道材料上加氢深度脱硫反应机理和规律；并采用动力学扩散模型，系统研究不同尺度和结构的模型硫化物分子在梯级孔道材料中的扩散规律。通过细致系统的研究，确定了BK复合材料的最佳合成方案，探究了模型硫化物在NiMo/BK催化剂上的反应机理，并通过动力学研究明晰了三维立方介孔NiMo/BK催化剂扩散性优于传统NiMo/Al2O3催化剂的本质，实验证实DBT在NiMo/BK上的转化率约为在NiMo/KIT-6上的3.8倍，为实现超清洁柴油加氢精制催化剂的设计合成及结构优化提供了科学研究基础和理论指导。