CeO_2改性的Ni_2P催化剂加氢脱硫反应性能

Hydrodesulfurization Performance of Ni_2P Catalysts Modified by CeO_2

以二苯并噻吩(DBT)的十氢萘溶液(DBT 质量分数为O.8%)为模型化合物,考察了 CeO_2改性的 Ni_2P 催化剂加氢脱硫(HDS)反应性能,并用 X 射线衍射(XRD)和程序升温还原(TPR)对催化剂进行了表征。XRD 结果表明,CeO_2的引入抑制了 Ni_5P_4杂晶的生成,Ni_2P 催化剂的晶粒尺寸随 CeO_2含量的增加而降低。TPR 结果显示,在 CeO_2与 Ni_2P 催化剂前驱体之间存在较强的相互作用,虽然抑制了NiO 的还原,但促进了 Ni_2P 物种的生成。从 DBT 的 HDS 反应结果可以看出,CeO_2对于 Ni_2P 加氢脱硫催化剂是一种有效的助剂,它的引入同时促进了 Ni_2P 催化剂直接脱硫(DDS)和加氢(HYD)路径反应活性,从而提高了催化剂 HDS 活性。其中,催化剂的 HYD 反应活性随 CeO_2含量的变化规律与催化剂晶粒尺寸变化规律相似,说明 Ni_2P 催化剂 HYD 反应活性对催化剂结构变化较为敏感。

The hydrodesulfurization （HDS） performances of CeO2-modified Ni2P catalysts was studied using dibenzothiophene （DBT） in decalin （mass fraction 0. 8G） as a model fuel. The catalysts were characterized by means of XRD （X-ray diffraction） and temperature programmed reduction （TPR）. The XRD results indicated that the formation of Ni5P4 was depressed by the introduction of CeO2, and the particle size of Ni2P decreased with the increasing of CeO2 mass fraction. Strong interaction between CeO2 and precursors of Ni2P was observed. The interaction slowed down the reduction of NiO but promoted the formation of Ni2P. The results of HDS of DBT indicated that CeO2 is a promising promoter for Ni2P. Both the direct desulfurization path （DDS） and hydrogenation path （HYD） were enhanced by the introduction of CeO2, and therefore leading to the improved HDS activity. The correlation between HYD activity and particle size of catalysts suggested that the HYD activity of Ni2 P was more sensitive to the structure of the catalysts.