Abstract:

NiS _x /γ-Al₂O₃-TiO₂ catalysts were modified with different contents of Mo by equal volume impregnation method, and their desulfurization performance was investigated on a fixed bed hydrogenation unit with dibenzothiophene (DBT) as the model compound. The catalysts were characterized by specific surface and porosity analyzer, X-ray diffraction (XRD), temperature programmed H₂ reduction (H₂-TPR), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). The results showed that the introduction of Mo did not change the crystal structure, but increased the specific surface area and pore size of the catalyst, which was conducive to the adsorption of sulfur-containing compounds on the catalyst surface. With the increase of Mo content, the catalyst showed better desulfurization activity and stability, and improved hydrogen hydrolysis performance. The hydrogenation selectivity showed a trend of decreasing first and then increasing, and the removal rate of DBT was higher than 99%. The catalyst was evaluated for low sulfur diesel oil, and the sulfur and nitrogen contents of diesel oil after reaction were less than 1μg/g, yielding nearly sulfur free diesel oil. It demonstrates promising industrial prospects.

Key words: catalyst, dibenzothiophene, hydrodesulfurization, petroleum

摘要：

以等体积浸渍法制备了不同含量Mo修饰的NiS _x /γ-Al₂O₃-TiO₂催化剂（NiMo/γ-Al₂O₃-TiO₂），以二苯并噻吩（DBT）为模型化合物，在固定床加氢装置上考察了系列催化剂的脱硫性能。采用比表面及孔隙度分析仪、X射线衍射（XRD）、H₂程序升温还原（H₂-TPR）、X射线光电子能谱（XPS）、高分辨透射电子显微镜（HRTEM）等分析手段对催化剂进行表征。结果表明，Mo的引入没有改变催化剂的晶相结构，增加了催化剂的比表面积和孔径，有利于含硫化合物在催化剂表面的吸附。随着Mo含量的增加，催化剂表现出更好的脱硫活性和稳定性，氢解性能得到了提高，加氢选择性呈现先降低后增大的趋势，对DBT的脱除率达到99%以上。将催化剂用于低硫柴油脱硫脱氮性能的评价，反应后柴油硫氮含量均低于1μg/g，能够用于生产近无硫柴油，显示出良好的工业前景。

关键词: 催化剂, 二苯并噻吩, 加氢脱硫, 石油