分散型纳米二硫化钼的制备及其对模拟油浆的加氢处理催化性能

以二烷基二硫代氨基甲酸钼（Mo-DTC）和六羰基钼（Mo（CO）₆）为前驱体、水热法合成了分散型纳米MoS₂，采用X-ray射线衍射（XRD）、透射电子显微镜（TEM）、X射线光电子能谱分析（XPS）和程序升温脱附法（NH₃-TPD）等方法对其进行了表征。利用三种烯烃（辛烯、苯乙烯、反式二苯乙烯）、苯并噻吩和蒽等构建模拟油浆体系，结合气相色谱-质谱（GC-MS）分析，对分散型纳米MoS₂的模拟油浆加氢处理催化性能进行了研究。结果表明，不同预处理条件下制备出的催化活性样品均为2H-MoS₂，但各样品的结晶度、颗粒尺寸、硫化程度及其酸性质等均有所不同，其中，总酸量差别较小；以Mo-DTC和Mo（CO）₆为前驱体的优选硫化条件分别为380℃/30 min 和370℃/30 min，所得到的催化剂对烯烃和噻吩的加氢活性较高。其中，Mo-DTC基纳米MoS₂催化剂的烯烃加氢饱和转化率高达98.10%，加氢脱硫率为94.51%，而蒽的部分加氢饱和转化率则较低，为29.47%，且无八氢蒽（8HN）或全氢蒽的生成。Mo（CO）₆基纳米MoS₂催化剂的加氢效果则略差，烯烃加氢饱和转化率为94.01%，加氢脱硫率为89.01%，对蒽的加氢饱和转化率为24.20%，无8HN或全氢蒽的生成。总体而言，由Mo-DTC所制备的MoS₂催化剂具有烯烃高效饱和、含硫化合物高效脱硫、芳烃浅度加氢饱和的效果，且油浆加氢处理反应的选择性及催化稳定性均更高。

Synthesis of dispersed molybdenum disulfide nano-catalysts and their performance in the hydrogenation of simulated oil slurry

A series of dispersed nano molybdenum disulfide (MoS₂) catalysts were prepared with molybdenum dialkyl dithiocarbamate (Mo-DTC) and molybdenum hexacarbonyl (Mo(CO)₆) as the precursors by hydrothermal methods and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (NH₃-TPD). By using a simulated oil slurry containing three kinds of olefins (octane, styrene and trans-dibenzylethene), benzothiophene and anthracene, the catalytic performance of nano MoS₂ in the hydrogenation was investigated, with the help of gas chromatography-mass spectrometry (GC-MS). The results indicate that all the prepared catalysts are in the form of 2H-MoS₂; however, their crystallinity, particle size, vulcanization degree, and acid property are influenced by the pretreatment conditions; the preferred vulcanization conditions for the Mo-DTC-and Mo(CO)₆-based MoS₂ catalysts are 380 ℃/30 min and 370 ℃/30 min, respectively, to achieve a relatively high activity in the hydrogenation of olefins and benzothiophene. Over the Mo-DTC-based nano-MoS₂ catalyst, the saturation conversion of olefins hydrogenation is 98.10% and the hydrodesulfurization rate is 94.51%, whereas the saturation conversion of anthracene hydrogenation is 29.47%, without forming octahydroanthracene (8HN) or perhydroanthracene. In contrast, the activity of Mo(CO)₆-based nano-MoS₂ catalyst is slightly lower, with the saturation conversion of olefins hydrogenation being 94.01% and the hydrodesulfurization rate being 89.01%; similarly, the saturation conversion for anthracene hydrogenation is 24.20%, without 8HN or perhydroanthracene in the product. As a whole, in comparison with the Mo(CO)₆-based MoS₂ catalyst, the nano MoS₂ catalyst derived from Mo-DTC displays higher efficiency in both olefins saturation and sulfur-containing compounds desulfurization, and low degree hydrogenation of aromatic hydrocarbons; moreover, it also exhibits higher hydro-treating selectivity for the catalytic cracking slurry and higher stability during hydrogenation.