Ni/CNT/Zeolite-Y composite catalyst for efficient heptane hydrocracking: Steady-state and transient kinetic studies

Abstract The effect of integrating carbon nanotubes (CNTs) into a bi-functional Ni-Zeolite-Y catalyst was studied for the hydrocracking of heptane at 350 and 400°C (total pressure of 5 bar). It was shown that the growth of CNTs on the surface of Ni-Zeolite-Y (Ni-ZY) results in enhanced stability and catalytic activity (conversion increased by 22% at 350°C) compared to the conventional Ni-ZY. A significant increase in the initial transient kinetic rates of CH4 and C2H6 formation was also noticed. The CNT/Ni-ZY also showed reduced coke formation during the reaction as entailed by transient isothermal (400 oC) oxidation experiments. The formation of a crystalline NixCy phase on the zeolite surface was observed in the case of CNT/Ni-ZY, potentially responsible for its enhanced catalytic performance. This work demonstrates that the integration of CNTs in hydrocracking catalysts offers new opportunities for enhancing their catalytic activity, selectivity and coking resistance.