Novel yolk-shell (YS) mesoporous silica materials with different cavity sizes were successfully synthesized. Aluminium was bridged into the yolk-shell framework of silica by a post synthesis method to improve the acidity of YS, namely Al-YS. The corresponding NiMo/Al-YS catalysts were also fabricated and used in the hydrodesulfurization (HDS) reaction of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). The NiMo/Al-YS catalyst with the cavity size of 154 nm (NiMo/Al-YS-154) exhibits the superior conversions of DBT (99.2 %) and 4,6-DMDBT (96.1 %) at 340 °C, 4.0 MPa, 10 h−1, highest kHDS (13.4×10−4 mol g−1 h−1 for DBT and 8.9 mol g−1 h−1 for 4,6-DMDBT) and highest TOF for DBT (3.7 h−1) and 4,6-DMDBT (2.3 h−1) among the investigated catalysts. The appropriate cavity size of NiMo/Al-YS-154 catalyst plays the key role in obtaining its superior HDS catalytic performance. Furthermore, the possible reaction networks of DBT and 4, 6-DMDBT HDS over NiMo/Al-YS-x catalysts were also presented.
Bibliographical noteKAUST Repository Item: Exported on 2022-10-25
Acknowledgements: The authors acknowledge the financial supports from the National Science Foundation of China (U1908204, 91845201, and 22002093), Scientific Research Project of Education Department of Liaoning Province (LQN202006) and King Abdullah University of Science and Technology (KAUST).