Hydrodesulfurization over NiMo Catalysts Supported on Yolk‐shell Silica Materials with Controllable Cavity Size

Abstract

AbstractNovel 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.