Preparation and Characterization of Core–Shell Composite Zeolite BEA@MFI and Their Catalytic Properties in ESR

Abstract

A group of BEA@MFI core–shell zeolite catalysts were successfully constructed with Cu-, Ni-modified Beta core and Co-based Silicalite-1 shell by combining seed induction secondary growth technique and incipient wetness impregnation method. The resulting micro-composite possess a well-defined core–shell structure with high surface area and abundant mesopore in the outer shell, and a relative large truncated bi-pyramidal shape core of Beta. It was further used to correlate their performance in ethanol steam reforming. The obtained xNiyCu-Beta@Co-Silicalite-1 catalysts exhibited excellent catalytic performance compared with the conventional zeolite catalysts. Particularly, the 2.5Ni2.5Cu-Beta@CoSilicalite-1 catalyst exhibited the highest selectivity of hydrogen, the lowest selectivity of by-products, the long-term stability and coking-resistance capability. This is mainly attributed to the excellent textural properties. And the Ni, Cu nanoparticles which incorporated into the core–shell micro-composites protected the properties of active phases effectively. Moreover, the “purification effect” of the Co-base shell is conducive to obtaining high-purity hydrogen through a multiple reaction system.