Ni-hierarchical Beta zeolite catalysts were applied to ethanol steam reforming: Effect of sol gel method on loading Ni and the role of hierarchical structure

Abstract

This paper describes the synthesis of Ni-hierarchical Beta zeolite catalysts (denoted as Ni-MBeta) via a sol-gel incipient wetness impregnation (SIWI) method and their application in ethanol steam reforming. Various techniques including N2 adsorption–desorption (BET), the powder X-ray diffraction (PXRD), H2 temperature programmed reduction (H2-TPR), Transmission electron microscopy (TEM) and Scanning electron microscope (SEM) with EDX were employed to characterize the fresh and spent catalysts. The results showed that intracrystalline mesoporous structure could improve mass-transfer efficiency and decrease the deactivation rate. Furthermore, loading Ni by SIWI method could effectively control the particle size of Ni via strong interaction between metals and support, thus further promoting the homogeneous distribution of Ni to achieve large interface. The effect of the properties of Ni loading on the catalysts was also investigated. Results have shown the catalyst with 15% Ni was the optimized composition owing to its strong metal-support interaction and high nickel active surface area. The stability of ethanol steam reforming was enhanced because of hierarchical structure and the loading method of SIWI. Consequently, the Ni-MBeta(G) catalyst exhibited superior activity with respect to the reference Ni-MBeta(N) catalyst and Ni-Beta(G) catalyst.