Development of radioactive ^<35>S and ^3H pulse tracer methods-Elucidation of behaviors of sulfur and hydrogen on sulfided catalysts

本研究是教育部科学、体育和文化部科学研究资助项目(B)(2)，项目编号08455371，为期两年（1996-1997）。本文综述了采用^<35>S和^3H放射性同位素脉冲示踪法对硫化催化剂结构和轻气油深度加氢脱硫机理的研究成果。虽然已有一些利用常规表征技术和动力学分析方法对HDS机理进行阐述的研究，但关于HDS催化剂结构和机理的许多基本观点仍有待阐明。特别是，很少有实例阐明硫在工作催化剂上的行为。为了不断开发新型催化剂，有必要更详细地了解加氢脱硫机理。另一方面，在实际的加氢脱硫反应中，用示踪剂方法可以量化硫在工作催化剂上的行为和氢的行为。因此，本研究开发了一种^<35>S和^3H放射性同位素脉冲示踪方法，并应用于以下几个方面：1)no基脱硫催化剂的预硫化机理；2)二苯并噻吩在钼基催化剂上加氢脱硫动力学；3) h2s和溶剂对加氢脱硫反应的缓速作用；4)用^<35>S脉冲示踪法解析钼基催化剂加氢脱硫过程中硫的迁移率；6)以负载型金属羰基配合物为催化前体的新型脱硫催化剂。通过这些研究，对硫化催化剂的结构、活性位点和加氢脱硫机理有了新的认识。这对开发适用于轻质油深度加氢脱硫的新型催化剂有很大的启示。少

This research was supported by grants from the Ministry of Education, Science, Sports and Culture as Grant-in-Aid for Scientific Research (B) (2) with the project number 08455371 in the two years (1996-1997). This report summarized the study results on the structure of sulfided catalysts and the mechanism of deep hydrodesulfurization of a light gas oil using ^<35>S and ^3H radioisotope pulse tracer methods. Many basic point on the structure of HDS catalyst and the mechanism have still remained to be clarified although a number of studies on elucidation of HDS mechanisms using conventional characterization technique and the kinetic analysis method were reported. Especially, there have been few examples clarifying the behavior of sulfur on the working-catalyst. In order to develop the new catalysts continuously, it is essential to know in more detail the hydrodesulfurization mechanism. On the other hand, the tracer method has been considered to enable us quantify the behavior of sulfur o … More n the working catalyst and hydrogen behavior in the practical hydrodesulfurization reaction. Therefore, in this study, a ^<35>S and ^3H radioisotope pulse tracer method was developed and was applied to several aspects as follows : 1) Presulfidation mechanism of No-based desulfurization catalysts ; 2) Hydrodesulfurization kinetics of dibenzothiophenes on Mo-based catalysts ; 3) Retarding effect of H_2S and solvent on hydrodesulfurization reaction ; 4) Elucidation of sulfur mobility on Mo-based catalysts in hydrodesulfurization by ^<35>S pulse tracer method : 5) Deep desulfurization mechanism of light gas oil ; 6) Novel desulfurization catalysts using supported metal carbonyl complexes as catalytic precursors. From these studies, a lot of new information on the structure of sulfided catalysts, the insight of active sites and the mechanism of hydrodesulfurization was obtained. This makes us gain a good deal of enlightenment for development of new catalysts appropriated to the dep hydrodesulfurization of light gas oil. Less