One-step synthesis of mesoporous alumina-supported molybdenum carbide with enhanced activity for thiophene hydrodesulfurization

A new mesoporous alumina-supported molybdenum carbide (Mo2C/γ-MA) has been successfully prepared by one-step hydrolysis method without template, followed by carbonization with a mixed gas of CH4 and H2. The Mo2C particles (2.5 ± 0.3 nm) are homogeneously dispersed in the γ-alumina (γ-MA) framework and exhibit high catalytic activity and stability for thiophene hydrodesulfurization (HDS). Taking 1 wt% thiophene (3810 ppm S) as an example, the Mo2C/γ-MA exhibits 92% thiophene conversion, higher than the MoS2/γ-MA (85%), and other molybdenum carbides supported over commercial alumina and γ-MA prepared by the impregnation method. The stability test demonstrated that the Mo2C/γ-MA almost showed no deactivation during 150 h reaction, and no obvious carbon deposition and sulfurization of Mo2C species were observed over the spent Mo2C/γ-MA. The high HDS activity and stability of the Mo2C/γ-MA for HDS could be attributed to the formation of small Mo2C nanoparticles, appropriate surface acidity and the strong interaction between Mo2C species and alumina inhibiting the sulfurization of Mo2C species.