不同还原时间制备的WP/γ-Al_2O_3催化剂表征及加氢精制性能

Characterization and Hydrotreating Performance of WP/γ-Al_2O_3 Catalysts Prepared with Different Reduction Time

采用共浸渍和程序升温高纯氢气还原的方法合成了WP/γ-Al2O3催化剂,对催化剂进行了XRD、BET和XPS表征,考察了还原时间对催化剂结构的影响。通过高压微反对催化剂的二苯并噻吩加氢脱硫和咔唑加氢脱氮活性进行了评价。结果表明:增加还原时间,有利于提高活性组分在载体表面的分散度,有利于增加催化剂的比表面积。还原时间增加,催化剂表面的P/W原子比提高,表面高价态的W6+所占比例增加,而氧化态的P5+所占比例有所降低。二苯并噻吩HDS活性和咔唑HDN活性都随催化剂还原时间的增加而提高。磷化钨催化剂更有利于大分子化合物的HDN反应,是一个良好的HDN催化剂。

WP/γ-Al2O3 catalysts were prepared by impregnation and temperature programmed reduction in H2. The catalysts were characterized by XRD,BET and XPS. The effect of reduction time of catalyst on the structure of catalysts was studied. The dibenzothiophene hydrodesulfurization and carbazole hydrodenitrogenation activities of catalysts were tested on a high pressure micro-reactor. The results showed that dispersion of active species and BET surface area were improved with the increase of reduction time. The P/W atomic ratio and the percentage of high valence of W^6＋ on the catalysts surface were increased by increasing the reduction time, while the percentage of P^5＋ was decreased. In favor of big molecular HDN reaction, Tungsten phosphide catalyst was a good performance HDN catalyst.