论文部分内容阅读
采用分步浸渍法制备了不同磷含量的MoNiP/γ-Al2O3加氢预处理催化剂。采用TPR、HRTEM和XPS技术对催化剂进行表征,以噻吩和喹啉为模型化合物,考察催化剂的加氢脱硫和加氢脱氮活性。结果表明,磷与活性组分相互作用形成新Mo-Ni-O-P相,增加了低温还原峰面积,使还原峰峰顶温度升高。磷的引入提高了活性金属组分的硫化度,使催化剂的MoS2片晶层数更多,片层长度更长,有助于噻吩和喹啉克服空间位阻吸附在活性中心位上;但过量磷会使MoS2发生团聚,降低活性中心位数目,不利于提高催化剂活性。添加适量磷对催化剂表面和活性相进行有限度的改变,使催化剂具有最佳的脱硫和脱氮活性。
MoNiP / γ-Al2O3 hydrotreating catalysts with different phosphorus contents were prepared by a stepwise impregnation method. The catalysts were characterized by TPR, HRTEM and XPS techniques. Thiophene and quinoline were used as model compounds to investigate the hydrodesulfurization and hydrodenitrogenation activities of the catalysts. The results show that the interaction between phosphorus and active components to form a new Mo-Ni-O-P phase, an increase of low-temperature reduction peak area, the reduction peak top temperature. The introduction of phosphorus increased the degree of sulfidation of the active metal component, making the catalyst more lamellar MoS2 lamellae and longer sheet length, which helped to overcome the steric hindrance of thiophene and quinoline on the active center. However, excess Phosphorus will agglomerate MoS2, reducing the number of active sites, is not conducive to improving the catalytic activity. Addition of appropriate amount of phosphorus on the catalyst surface and the active phase of a limited change, so that the catalyst has the best desulfurization and denitrification activity.